bluuebunny/crossref_metadata_2025 huggingface dataset:
Suppression of humoral immune responses by 2,3,7,8-tetrachlorodibenzo-p-dioxin intercalated in smectite clay
Authors: Boyd Stephen A , Johnston Cliff T , Pinnavaia Thomas J , Kaminski Norbert E , Teppen Brian J , Li Hui , Khan Bushra , Crawford Robert B , Kovalova Natalia , Kim Seong-Su , Shao Hua , Gu Cheng , Kaplan Barbara L.F
Published: October 2011

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a highly toxic environmental contaminant found in soils and sediments. Because of its exceptionally low water solubility, this compound exists predominantly in the sorbed state in natural environments. Clay minerals, especially expandable smectite clays, are one of the major component geosorbents in soils and sediments that can function as an effective adsorbent for environmental dioxins, including TCDD. In this study, TCDD was intercalated in the smectite clay saponite by an incipient wetness method. The primary goal of this study was to intercalate TCDD in natural K-saponite clay and evaluate its immunotoxic effects in vivo. The relative bioavailability of TCDD was evaluated by comparing the metabolic activity of TCDD administered in the adsorbed state as an intercalate in saponite and freely dissolved in corn oil. This comparison revealed nearly identical TCDD-induced suppression of humoral immunity, a well-established and sensitive sequela, in a mammalian (mouse) model. This result suggests that TCDD adsorbed by clays is likely to be available for biouptake and biodistribution in mammals, consistent with previous observations of TCDD in livestock exposed to dioxin-contaminated ball clays that were used as feed additives. Adsorption of TCDD by clay minerals does not appear to mitigate risk associated with TCDD exposure substantially. Environ. Toxicol. Chem. 2011;30:2748–2755. © 2011 SETAC
Solubility of nano-zinc oxide in environmentally and biologically important matrices
Authors: Reed Robert B. , Ladner David A. , Higgins Christopher P. , Westerhoff Paul , Ranville James F.
Published: October 2011

Increasing manufacture and use of engineered nanoparticles is leading to a greater probability for release of engineered nanoparticles into the environment and exposure to organisms. In particular, zinc oxide (ZnO) is toxic, although it is unclear whether this toxicity is due to the zinc oxide nanoparticles, dissolution to Zn2+, or some combination thereof. The goal of this study was to determine the relative solubilities of both commercially available and in-house synthesized ZnO in matrices used for environmental fate and transport or biological toxicity studies. Dissolution of ZnO was observed in nanopure water (7.18–7.40 mg/L dissolved Zn, as measured by filtration) and Roswell Park Memorial Institute medium (RPMI-1640) (∼5 mg/L), but much more dissolution was observed in Dulbecco's modified Eagle's medium, in which the dissolved Zn concentration exceeded 34 mg/L. Moderately hard water exhibited low Zn solubility, likely because of precipitation of a Zn carbonate solid phase. Precipitation of a Zn-containing solid phase in RPMI also appeared to limit Zn solubility. Equilibrium conditions with respect to ZnO solubility were not apparent in these matrices, even after more than 1,000 h of dissolution. These results suggest that solution chemistry exerts a strong influence on ZnO dissolution and can result in limits on Zn solubility from precipitation of less soluble solid phases. Environ. Toxicol. Chem. 2012;31:93–99. © 2011 SETAC
Methodological considerations for testing the ecotoxicity of carbon nanotubes and fullerenes: Review
Authors: Petersen Elijah J. , Henry Theodore B.
Published: October 2011

The recent emergence of manufactured nanoparticles (NPs) that are released into the environment and lead to exposure in organisms has accelerated the need to determine NP toxicity. Techniques for measuring the toxicity of NPs (nanotoxicology) in ecological receptors (nanoecotoxicology) are in their infancy, however, and establishing standardized ecotoxicity tests for NPs are presently limited by several factors. These factors include the extent of NP characterization necessary (or possible) before, during, and after toxicity tests such that toxic effects can be related to physicochemical characteristics of NPs; determining uptake and distribution of NPs within exposed organisms (does uptake occur or are effects exerted at organism surfaces?); and determining the appropriate types of controls to incorporate into ecotoxicity tests with NPs. In this review, the authors focus on the important elements of measuring the ecotoxicity of carbon NPs (CNPs) and make recommendations for ecotoxicology testing that should enable more rigorous interpretations of collected data and interlaboratory comparisons. This review is intended to serve as a next step toward developing standardized tests that can be incorporated into a regulatory framework for CNPs. Environ. Toxicol. Chem. 2012;31:60–72. © 2011 SETAC
Reproductive and behavioral responses of earthworms exposed to nano-sized titanium dioxide in soil
Authors: McShane Heather , Sarrazin Manon , Whalen Joann K. , Hendershot William H. , Sunahara Geoffrey I.
Published: October 2011

Nanometer-sized titanium dioxide (nano-TiO2) is found in a number of commercial products; however, its effects on soil biota are largely unknown. In the present study, earthworms (Eisenia andrei and Eisenia fetida) were exposed to three types of commercially available, uncoated TiO2 nanomaterials with nominal diameters of 5, 10, and 21 nm. Nanomaterials were characterized for particle size, agglomeration, surface charge, chemical composition, and purity. Standard lethality, reproduction, and avoidance tests, as well as a juvenile growth test, were conducted in artificial soil or field soil amended with nano-TiO2 by two methods, liquid dispersion and dry powder mixing. All studies included a micrometer-sized TiO2 control. Exposure to field and artificial soil containing between 200 and 10,000 mg nano-TiO2 per kilogram of dry soil (mg/kg) had no significant effect (p > 0.05) on juvenile survival and growth, adult earthworm survival, cocoon production, cocoon viability, or total number of juveniles hatched from these cocoons. However, earthworms avoided artificial soils amended with nano-TiO2. The lowest concentration at which avoidance was observed was between 1,000 and 5,000 mg nano-TiO2 per kilogram of soil, depending on the TiO2 nanomaterial applied. Furthermore, earthworms differentiated between soils amended with 10,000 mg/kg nano-TiO2 and micrometer-sized TiO2. A positive relationship between earthworm avoidance and TiO2 specific surface area was observed, but the relationship between avoidance and primary particle size was not determined because of the agglomeration and aggregation of nano-TiO2 materials. Biological mechanisms that may explain earthworm avoidance of nano-TiO2 are discussed. Results of the present study indicate that earthworms can detect nano-TiO2 in soil, although exposure has no apparent effect on survival or standard reproductive parameters. Environ. Toxicol. Chem. 2012;31:184–193. © 2011 SETAC
A mild and efficient protocol for oxidation of thiols to disulfides in water
Authors: Dewan Anindita , Bora Utpal , Kakati Dilip K.
Published: October 2011

A novel vanadium polyoxometalate [(C7H7)(CH3)3N]3[H3V10O28].3H2O works as a useful oxidant for the oxidation of thiols to disulfldes in water under mild reaction conditions in an excellent yield. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:231–234, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20760
Vitamin D deficiency in obese rats exacerbates nonalcoholic fatty liver disease and increases hepatic resistin and toll-like receptor activation
Authors: Roth Christian L. , Elfers Clinton T. , Figlewicz Dianne P. , Melhorn Susan J. , Morton Gregory J. , Hoofnagle Andrew , Yeh Matthew M. , Nelson James E. , Kowdley Kris V.
Published: October 2011

Childhood obesity is associated with type 2 diabetes mellitus and nonalcoholic fatty liver disease (NAFLD). Recent studies have found associations between vitamin D deficiency (VDD), insulin resistance (IR), and NAFLD among overweight children. To further explore mechanisms mediating these effects, we fed young (age 25 days) Sprague-Dawley rats with a low-fat diet (LFD) alone or with vitamin D depletion (LFD+VDD). A second group of rats was exposed to a Westernized diet (WD: high-fat/high-fructose corn syrup) that is more typically consumed by overweight children, and was either replete (WD) or deficient in vitamin D (WD+VDD). Liver histology was assessed using the nonalcoholic steatohepatitis (NASH) Clinical Research Network (CRN) scoring system and expression of genes involved in inflammatory pathways were measured in liver and visceral adipose tissue after 10 weeks. In VDD groups, 25-OH-vitamin D levels were reduced to 29% (95% confidence interval [CI]: 23%-36%) compared to controls. WD+VDD animals exhibited significantly greater hepatic steatosis compared to LFD groups. Lobular inflammation as well as NAFLD Activity Score (NAS) were higher in WD+VDD versus the WD group (NAS: WD+VDD 3.2 ± 0.47 versus WD 1.50 ± 0.48, P < 0.05). Hepatic messenger RNA (mRNA) levels of Toll-like receptors (TLR)2, TLR4, and TLR9, as well as resistin, interleukins (IL)-1β, IL-4, and IL-6 and oxidative stress marker heme oxygenase (HO)-1, were higher in WD+VDD versus WD animals (P < 0.05). Logistic regression analyses showed significant associations between NAS score and liver mRNA levels of TLRs 2, 4, and 9, endotoxin receptor CD14, as well as peroxisome proliferator activated receptor (PPAR)γ, and HO-1. Conclusion: VDD exacerbates NAFLD through TLR-activation, possibly by way of endotoxin exposure in a WD rat model. In addition it causes IR, higher hepatic resistin gene expression, and up-regulation of hepatic inflammatory and oxidative stress genes. (Hepatology 2012)
Natural Bond Orbital Rationalizations of NMR Observations for Metal‐Ligand Bonding (II): Rehybridization of Phosphorus Arising from Coordination of Methyl‐Phenyl‐Phosphines
Authors: Su Wei‐Lin , Huang Hsiu‐Ping , Chen Wei‐Ting , Hsu Wen‐Yi , Chang Hsi‐Yen , Ho Szu‐Yu , Wang Shao‐Pin , Shyu Shin‐Guang
Published: October 2011

Carbonyls' 2π orbital populations, [2π], in W(CO)5L {L = PPh3, PPh2Me, PPhMe2} have been determined by NMR spin‐lattice relaxation techniques. Experimental values of axial [2π], compared with those reported for PMe3 and P(OMe)3, reveal that PMe3 is a slightly better π‐acid than PPh3. Through space interactions between carbonyl and phenyl groups are insignificant since values of [2π] do not vary significantly in the series of phosphines, going from PMep3 to PPh3. Natural bond orbital (NBO) studies indicate that π‐accepting capabilities for these phosphines are primarily governed by the nature of P‐C anti‐bonding, σ*P‐C. Compared with PPh3, the better π‐accepting σ*P‐C, as well as the better s‐donating lone‐pair LP(P), in PMe3 can both be explained by the higher extents of rehybridization of the coordinated phosphorus atom. Based on this rehybridization argument, the NBO predicted order of increasing π‐acidic strengths PPh3 < PPh2Me < PPhMe2 < PMe3, which cannot be clearly distinguished by NMR experiments, is ascribed to the same NBO trend of σ‐donating capabilities in a synergistic manner. Effects of coordination on P‐Y (Y = C, O, F) bonding strengths in phosphines (or phosphites) are depending on two conflicting effects: rehybridization of LP(P) and the hyperconjugative‐like dπ → σ*P‐Y back‐donation.
Validated Method for the Simultaneous Determination of Gemifloxacin and H2‐receptor Antagonists in Bulk, Pharmaceutical Formulations and Human Serum by RP‐HPLC; In‐vitro Applications
Authors: Sultana Najma , Arayne M. Saeed , Shamim Sana , Naz Asia
Published: October 2011

Simple, isocratic and rapid RP‐HPLC method has been developed for the simultaneous analysis of gemifloxacin and H2‐receptor antagonists i.e. Cimetidine, Famotidine and Ranitidine, in bulk, pharmaceutical formulation and human serum. Separation was achieved on the RP‐Mediterranea column [C18 (250 × 4.6 mm, 5 μ)] at ambient temperature using mobile phase consisting of acetonitrile: methanol: water (20:28:52 v/v/v pH 2.8 adjusted by phosphoric acid). Flow rate was 1.0 mL/min with an average operating pressure of 180 kg/cm2. Gatifloxacin (GATI) was used as an internal standard (IS). Quantitation was achieved with UV detection at 221, 256 and 267 nm, respectively. Linear calibration curves, at concentration ranges of 0.05‐37.5 μgmL‐L with a correlation coefficient of ±0.9994. The detection and quantification limits were in the ranges of 0.023‐0.250 μgmL‐L and 0.071‐0.756 μgmL‐L, respectively. Friedman's and Student's t‐test were applied to correlate these results. Method was validated in terms of selectivity, linearity, precision, robustness, recovery, limits of detection and quantitation and is applicable to the routine analysis of GFX and H2‐receptor antagonists, alone or in combination.
Implementation of a TORS program in an academic medical center
Authors: Richmon Jeremy D. , Agrawal Nishant , Pattani Kavita M.
Published: October 2011

Objectives:

Transoral robotic surgery (TORS) is rapidly being adopted by many head and neck surgeons for treatment of upper aerodigestive tract tumors. Various obstacles exist to efficiently implement this novel surgical technique in a busy academic center. We present our experience to illustrate one approach to initiating a TORS program.

Study Design:

Prospective cohort study.

Methods:

A clear, stepwise approach to introduce TORS in our hospital was devised prior to scheduling the first case. Upon initiation of the program, various time points and surgical outcomes were measured for all patients undergoing TORS.

Results:

The first 20 cases of TORS at Johns Hopkins Hospital are reviewed. Room setup time averaged 24 minutes (±12). Presurgery time averaged 22 ± 10 minutes. Positioning time averaged 38 ± 13 minutes. Operative time (OT) averaged 71 ± 54 minutes. The total time in room (TTR) averaged 242 ± 84 minutes. There were no significant differences (P > .5) in any of the time measurements above between the first and second 10 cases or the first 15 and last 5 cases. Negative margins (both frozen and permanent) were obtained in all ablative cases. No patient required a tracheotomy and no procedure was aborted secondary to inability to expose the tumor. The average hospitalization time was 1.3 days. All patients were discharged on oral diets. There were no long‐term surgical complications.

Conclusions:

The introduction of a TORS program in an academic medical center can be a complex and daunting undertaking. We demonstrate that with careful planning, excellent efficiency and safety can be attained immediately.
Effective use of physician extenders in an outpatient otolaryngology setting
Authors: Norris Byron , Harris Tristen , Stringer Scott
Published: October 2011

Physician extenders may be a valuable asset to an outpatient otolaryngology practice. The adjunctive care provided by physician extenders appears to be cost effective and has the advantages of increasing patient education, promoting physician productivity, and improving management of chronic conditions. Practice types that may benefit from advanced practice providers include group or solo practices with high demand or who need improved efficiency. We discuss five different practice models for incorporation of advanced practice providers in an outpatient otolaryngology practice. These models include scribe, collaborative, limited independent, partial independent, and near complete independent practice and are based primarily on the autonomy level of the physician extender. In additon, we examine available literature discussing the cost effectiveness of physician extenders used in an outpatient setting.
Application of the control volume mixed finite element method to a triangular discretization
Authors: Naff R.L.
Published: October 2011

A two‐dimensional control volume mixed finite element method is applied to the elliptic equation. Discretization of the computational domain is based in triangular elements. Shape functions and test functions are formulated on the basis of an equilateral reference triangle with unit edges. A pressure support based on the linear interpolation of elemental edge pressures is used in this formulation. Comparisons are made between results from the standard mixed finite element method and this control volume mixed finite element method. Published 2011. This article is a US Government work and is in the public domain in the USA.
A level‐set‐based large sliding contact algorithm for easy analysis of implant positioning
Authors: Andreykiv Andriy , van Keulen Fred , Rixen Daniel J. , Valstar Edward
Published: October 2011

A finite element analysis of implant positioning inside a bone requires the creation of many meshes that model various implant orientations. This process can be very labour intensive and is difficult to automate. In order to facilitate this type of modelling, we present a large sliding contact algorithm that does not require the creation of a conforming discretization for the bone. The cavity inside the bone, necessary to accommodate the implant, is modelled with a Heaviside function calculated on the level set field, which is defined in terms of material coordinates of the bone. The algorithm is based on the minimization of the energy functional with a constraint term, formulated as in classical contact mechanics; however, instead of the distance function, we use the above‐mentioned level set function. The presented numerical 2D and 3D examples validate the algorithm against the solutions obtained with commercial finite element software. Copyright © 2011 John Wiley & Sons, Ltd.
Autophagy and disease: always two sides to a problem
Authors: Sridhar Sunandini , Botbol Yair , Macian Fernando , Cuervo Ana Maria
Published: October 2011

Autophagy is a process traditionally known to contribute to cellular cleaning through the removal of intracellular components in lysosomes. In recent years, intensive scrutiny at the molecular level to which autophagy has been subjected has also contributed to expanding our understanding of the physiological role of this pathway. Added to the well‐characterized role in quality control, autophagy has proved to be important in the maintenance of cellular homeostasis and of the energetic balance, in cellular and tissue remodelling, and cellular defence against extracellular insults and pathogens. It is not a surprise that, in light of this growing number of physiological functions, connections between autophagic malfunction and human pathologies have also been strengthened. In this review, we focus on several pathological conditions associated with primary or secondary defects in autophagy and comment on a recurring theme for many of them, ie the fact that autophagy can often exert both beneficial and aggravating effects on the progression of disease. Elucidating the factors that determine the switch between these dual functions of autophagy in disease has become a priority when considering the potential therapeutic implications of the pharmacological modulation of autophagy in many of these pathological conditions. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Lewis acidic polypropylene for compatibilization of polypropylene/microsilica composites
Authors: Lipponen Sami , Nykänen Antti , Ruokolainen Janne , Seppälä Jukka
Published: October 2011

Polypropylene (PP) was compounded with submicron size silica filler particles (microsilica, μSi) up to 30 wt‐%. In addition, three external compatibilizers, with characteristic functionalities, were studied to examine their influence in the mechanical properties of the PP/μSi composites. As a result, the modulus of the composite increased while the other tensile values deteriorated in correlation with increased filler concentration. The addition of an external compatibilizer reduced this deterioration, but the reduction was dependent on the type of the compatibilizer used. The influence of an acid functionalized compatibilizer was unsubstantial while the fluorosilane and the Lewis acidic phenylsilane functionalized polypropylenes acted as effective compatibilizers. In addition to examining the tensile properties, the toughness of the composites was evaluated as well. The microsilica filler was found to act as toughening agent since the Brittle‐to‐Ductile transition point of the composite increased by 2‐3 orders of magnitude at high filler concentrations. However, this increase in the toughness was rapidly lost when an effective compatibilizer was used to bind the filler with the matrix. This observation was consistent with the common understanding of the filler toughening mechanism, where particle‐matrix debonding is a prerequisite for facilitating the plastic stretch of the polymer ligaments between filler particles. In our case, however, the few filler aggregates in the polymer matrix also played a crucial role. While in uncompatibilized composites the filler aggregates remained passive (could not be seen at the fracture surface), the addition of an effective compatibilizer activated these aggregates to promote crack initiation and/or propagation. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
Novel POBD‐modified organoclay and its polyimide nanocomposites for removal of the Co(II) ion
Authors: Mansoori Yagoub , Fathollahi Kobra , Reza Zamanloo Mohammad , Imanzadeh Gholamhassan
Published: October 2011

An organophilic clay has been obtained via cation exchange reaction between sodium montmorillonite and the hydrochloride salt of 2‐(5‐(3,5‐diaminophenyl)‐1,3,4‐oxadiazole‐2‐yl)pyridine, POBD. Thermogravimetric analysis (TGA) showed that thermal decomposition of the organophilic clay starts at about 350°C, which shows that it is quite thermally stable compared with conventional montmorillonite modified with aliphatic long chain surfactants. POBD‐modified organoclay almost quantitatively removed the Co(II) ion from aqueous solution at pH = 10.0 (Qt = 3.00 mg g−1, R = 98.2%). A series of polyimide/clay nanocomposite materials (PCNs) consisting of POBD and benzophenone‐3,3′,4,4′‐tetracarboxylic dianhydride, BTDA were also prepared by an in situ polymerization reaction via thermal imidization. POBD‐modified organoclay was used as a surfactant at different concentrations. Intercalation of polymer chains within the organoclay galleries was confirmed by WXRD. Both the glass transition temperature and thermal stability are increased with respect to pristine PI at low clay concentrations. At high clay loadings, the aggregation of organoclay particles results in a decrease in Tg and thermal stability. In the SEM images of PCN 1 and 3%, too many micro cracks are observed in the background, and a flower‐shape pattern spreads uniformly over the entire surface. The maximum Co(II) uptake capacity and efficiency were observed at pH 10.0 within a 40‐h period for both PI and PCN films. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
Fabrication of porous poly(acrylamide) beads with macro‐ and micropores
Authors: Choi Sung‐Wook , Yeom Ji‐Yoon , Park Tae‐Joon , Lee Jun‐Young , Kim Jung‐Hyun
Published: October 2011

On the basis of an oil‐in‐water‐in‐oil emulsion, polyacrylamide (PAM) beads with a dual porous structure were fabricated using both an emulsion and polystyrene (PS) particles as templates. Uniform oil‐in‐water droplets dispersed in an oil phase (a sedimentation medium) were polymerized in a reaction glass column, where the water phase contained acrylamide and PS particles. Afterward, the cross‐linked PAM beads were immersed in n‐hexane and methanol to remove all of the oil phases and then in acetone and toluene to remove the PS particles, resulting in dual porous PAM beads. The PAM beads exhibited macropores (5–30 μm) and micropores (approximately 400 nm) that were developed by the removal of the inner oil phase and the PS particles, respectively. The employment of PS particles as templates resulted in a remarkable increase in the pore area from 2.2 to 6.3 m2/g. In addition, an increase in the volume ratio of the inner oil phase to the water phase for the primary oil‐in‐water emulsion led to an increase in the pore volume and a reduction in the pore area. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Review on Melt Cast Explosives
Authors: Ravi Pasupala , Badgujar Dilip M. , Gore Girish M. , Tewari Surya P. , Sikder Arun K.
Published: October 2011

A systematic overview of melt cast explosives is given. The research on melt cast explosives over several decades can be divided into three broad areas: (i) aromatic compounds with CCH3, NCH3, OCH3 CNO2, NNO2 and ONO2 groups, (ii) improved synthesis of compounds, which are currently used in formulations or which have shown promise for such use and (iii) the preparation of melt cast formulations with various compositions. Exudation, high volume change from liquid to solid, super cooling, irreversible growth, fragility and unpredictable sensitivity are the disadvantages of existing melt cast formulations.
Amphiphile replacement on carbon nanotube surfaces: Effect of aromatic groups on the interaction strength
Authors: Bluemmel Pascal , Setaro Antonio , Popeney Chris S. , Trappmann Britta , Haag Rainer , Reich Stephanie
Published: October 2011

Carbon nanotubes (CNTs) were solubilized using akyl/polyglycerol amphiphiles. Similar cosurfactants, bearing different aromatic moieties between head and tail, were added to these samples. The interaction strength between these amphiphiles and CNTs changes depending on the inserted aromatic moieties. The insertion of a phenyl ring allows the amphiphile to replace the starting one indicating a higher interaction strength, while the insertion of a triazol pentagon does not, suggesting that the interaction strength is lower. The replacement was monitored via PLE mapping.

magnified image
Electronic structure of EuO spin filter tunnel contacts directly on silicon
Authors: Caspers C. , Müller M. , Gray A. X. , Kaiser A. M. , Gloskovskii A. , Fadley C. S. , Drube W. , Schneider C. M.
Published: October 2011

We present an electronic structure study of a magnetic oxide/ semiconductor model system, EuO on silicon, which is dedicated for efficient spin injection and spin detection in silicon‐based spintronics devices.

A combined electronic structure analysis of Eu core levels and valence bands using hard X‐ray photoemission spectroscopy was performed to quantify the nearly ideal stoichiometry of EuO “spin filter” tunnel barriers directly on silicon, and the absence of silicon oxide at the EuO/Si interface. These results provide evidence for the successful integration of a magnetic oxide tunnel barrier with silicon, paving the way for the future integration of magnetic oxides into functional spintronics devices.

magnified image

Hard X‐ray photoemission spectroscopy of an Al/EuO/Si heterostructure probing the buried EuO and EuO/Si interface.

(© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rapid analysis of isomeric exogenous metabolites by differential mobility spectrometry – mass spectrometry
Authors: Parson Whitney B. , Schneider Bradley B. , Kertesz Vilmos , Corr Jay J. , Covey Thomas R. , Van Berkel Gary J.
Published: October 2011

The direct separation of isomeric glucuronide metabolites from propranolol dosed tissue extracts by differential mobility spectrometry – mass spectrometry (DMS‐MS) with the use of the polar gas‐phase chemical modifier acetonitrile was demonstrated. The DMS gas‐phase separation was able to resolve the isomeric metabolites with separation times on the order of milliseconds instead of minutes which is typically required when using pre‐ionization chromatographic separation methods. Direct separation of isomeric metabolites from the complex tissue extract was confirmed by implementing a high‐performance liquid chromatography (HPLC) separation prior to the DMS‐MS analysis to pre‐separate the species of interest. The ability to separate isomeric exogenous metabolites directly from a complex tissue extract is expected to facilitate the drug development process by increasing analytical throughput without the requirement for pre‐ionization cleanup or separation strategies. Published in 2011 by John Wiley & Sons, Ltd.
Barriers to prenatal detection of congenital heart disease: a population‐based study
Authors: Pinto N. M. , Keenan H. T. , Minich L. L. , Puchalski M. D. , Heywood M. , Botto L. D.
Published: October 2011

Objective

To evaluate the extent and determinants of missed prenatal detection of congenital heart disease (CHD) in a population‐based setting.

Methods

This was a retrospective cohort study of cases with CHD, excluding minor defects, identified between 1997 and 2007 by a statewide surveillance program. We examined a comprehensive list of potential risk factors for which data were available in the surveillance database from abstracted medical charts. We analyzed the association of fetal, maternal and encounter factors with 1) whether a prenatal ultrasound was performed and 2) prenatal detection of CHD.

Results

CHD was detected prenatally in only 39% of 1474 cases, with no improvement in detection rate over the 10‐year period. Among the 97% (n = 1431) of mothers who underwent one or more ultrasound examinations, 35% were interpreted as abnormal; fetal echocardiography was performed in 27% of the entire cohort. Maternal and encounter factors increasing the adjusted odds of prenatal detection included: family history of CHD (OR, 4.3 (95% CI, 1.9–9.9)), presence of extracardiac defects (OR, 2.7 (95% CI, 1.9–3.9)) and ultrasound location i.e. high risk clinic vs clinic (OR, 2.1 (95% CI, 1.3–3.1)). Defects that would be expected to have an abnormal outflow‐tract view were missed more often (64%) than were those that would be expected to have an abnormal four‐chamber view (42%).

Conclusion

The majority of CHD cases over the 10‐year study period were missed prenatally and detection rates did not increase materially during that time. The failure to detect CHD prenatally was related to encounter characteristics, specifically involving screening ultrasound examinations, which may be targeted for improvement. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Cassettes for PCR‐mediated gene tagging in Candida albicans utilizing nourseothricin resistance
Authors: Milne Stephen W. , Cheetham Jill , Lloyd Deborah , Aves Stephen , Bates Steven
Published: October 2011

In recent years a number of molecular tools have been reported for use in the human fungal pathogen Candida albicans, including PCR‐mediated approaches for gene disruption, conditional expression and epitope tagging. Traditionally these methods have utilized auxotrophic markers; however, the availability of auxotrophic markers can be limiting and in some instances their use may also impact on the interpretation of results. As a result, the use of positive selection markers has now become more commonplace. Here we report the development and validation of a set of cassettes for PCR‐mediated gene tagging and overexpression studies utilizing the nourseothricin resistance (CaNAT1) positive selection marker. In particular we have produced cassettes containing yeast‐enhanced GFP, YFP, CFP, RFP and a combined V5–6xHis epitope tag. The cassettes are engineered for use in PCR‐mediated gene tagging strategies where insertion is targeted to the 3′ end of the gene of interest. In addition, to facilitate protein functional analysis and genetic suppression studies through the use of overexpression, we have also constructed a promoter replacement cassette containing the ENO1 promoter which is known to be expressed at a high level. These cassettes expand on the range of molecular tools available for working with C. albicans and may also be used in other Candida species that display sensitivity to nourseothricin. Copyright © 2011 John Wiley & Sons, Ltd.
The origin of progesterone in blood when a bacterial solution is infused into the uterus of rats
Authors: Kaneko Kazuyuki , Takagi Nobuaki , Yamaguchi Shou , Yokoyama Mao , Shikita Mithuhiro , Takeuchi Yohoko , Sugimoto Kohoki , Sato Reiichiro
Published: October 2011

Purpose

The infusion of a bacterial solution into the uterus of rats raises the progesterone (P4) concentration in serum and extends diestrus. To understand the origin of the P4, we investigated the change in the P4 concentration of seven groups of rats for 5 days after the infusion of a bacterial solution.

Methods

The rats were divided into 7 treatment groups as follows: OvxBac, AdxBac, Ovx, Adx, LapBac, Lap, and Cont. In OvxBac, rats received both ovariectomy and bacterial inoculation into their uterus. In AdxBac, rats received both adrenalectomy and bacterial inoculation into their uterus. In Ovx, rats received only ovariectomy. In Adx, rats received only adrenalectomy. In LapBac, rats received only bacterial inoculation into their uterus. In Lap, rats received only laparotomy. In Cont, rats did not receive any treatment and acted as controls.

Results

The P4 concentration in all treatment groups was higher than in Cont on day 1 (the day following operation) and day 2. In Lap and LapBac, the P4 concentration was high on day 1 (>30 ng/mL) and maintained that value until day 2. In Adx and AdxBac, the P4 concentration was average on day 1 (approximately 25 ng/mL) and increased on day 2 to a value close to that of LapBac and Lap. In OvxBac, although the P4 concentration increased slightly on day 1 and day 2, it reached 22.5 ± 7.5 ng/mL on day 4. In AdxBac and LapBac, the P4 concentration on day 4 tended to be high.

Conclusion

These results suggest that P4 is initially secreted from the ovaries and the adrenals in response to the surgical stress of laparotomy, and is later secreted from the adrenals due to the inflammatory reaction of the uterus.
MIGRATION, TRANSLOCAL NETWORKS AND SOCIO-ECONOMIC STRATIFICATION IN NAMIBIA
Authors: Greiner Clemens
Published: October 2011

Rural–urban migration and networks are fundamental for many livelihoods in sub-Saharan Africa. Remittances in cash and kind provide additional income, enhance food security and offer access to viable resources in both rural and urban areas. Migration allows the involved households to benefit from price differences between rural and urban areas. In this contribution, I demonstrate that rural–urban networks not only contribute to poverty alleviation and security, but also further socio-economic stratification. This aspect has been ignored or neglected by most scholars and development planners. Using ethnographic data from Namibia, I have adopted a translocal perspective on migration and stratification, focusing on the resulting impact in rural areas where modern urban forms of stratification, induced by education and income from wage labour, are on the increase.
LOCAL REFORMERS AND THE SEARCH FOR CHANGE: THE EMERGENCE OF SALAFISM IN BALE, ETHIOPIA
Authors: Østebø Terje
Published: October 2011

Since 1991 Salafism has gained renewed strength in Ethiopia, spurred increased tensions within the Muslim community, and created concern among the Christian population. This contribution focuses on the early emergence of Salafism in the area of Bale, currently one of the movement's strongholds. It discusses its initial arrival in south-eastern Ethiopia, and pays particular attention to the developments in Bale during the 1960s. Challenging the notion that treats Islamic reform as seemingly homogeneous and as ‘foreign’ – distinctly separated from ‘local’ Islam – the contribution explores the arrival of the Salafi teaching from Saudi Arabia, and follows the process of reform embodied in an emerging group of local merchants and in graduates returning from studies in Saudi Arabia. The contribution highlights how socio-economic changes and developments of infrastructure facilitated the emergence of new groups of actors, transcending local boundaries and actively generating novel discourses about religious symbols and practices. It also demonstrates how a diversified body of situated actors was crucial for the appropriation and domestication of the Salafi message, and points to the trajectory of reform as a dialectical process of moulding that related such influences to the local context.
Voluntary ingestion of wood shavings by obese horses under dietary restriction
Authors: Curtis Gemma C. , Barfoot Clare F. , Dugdale Alexandra H. A. , Harris Patricia A. , Argo Caroline McG.
Published: October 2011

Dietary restriction for the weight-loss management of obese horses limits the natural trickle-feeding behaviour. During feed restriction, wood shavings are often advised as bedding to prevent dietary supplementation from non-feed sources. Data from twelve overweight/obese horses and ponies of mixed breed and sex, bedded on wood shavings during 16 weeks of feed restriction, were retrospectively evaluated. DM intake (DMI) was restricted to 1·25 % of body mass (BM) daily. Animals were randomly assigned to one of two diets (hay/chaff, n 6; hay/balancer meal, n 6). BM was recorded weekly. Feeding behaviour was recorded by continual observation over 24 h during week 15. The apparent digestibility (gross energy (GE), acid-detergent fibre (ADF) and DM) of feed was determined for all animals by total faecal collection (72 h, week 16). Rates of weight loss were independent of diet type, DM (R2 0·15), GE (R2 0·20) and ADF digestibilities (R2 0·18). Despite similar DMI, faecal DM ranged between 0·52 and 1·16 % of BM daily and was associated with wide ranges in apparent digestibility (GE − 11·34 to 53·08 %; ADF − 50·37 to 42·83 % and DM 2·14 to 57·32 %), which were improbably low for some animals. Apparent digestibilities were associated with DM output (GE R2 0·96; ADF R2 0·99 and DM R2 0·99) and time spent feeding (GE R2 0·62; DM R2 0·61 and ADF R2 0·59), indicating that feed intake was supplemented with wood shavings in at least five of the twelve animals. Quantities of wood shavings ingested (negligible to >3·0 kg/d) were back-calculated from predicted feed digestibilities. All animals remained healthy. Implications of ‘feed-bulking/energy dilution’ for feed-restricted animals need further consideration.
Challenges in developing nutrient guidelines for companion animals
Authors: Butterwick Richard F. , Erdman John W. , Hill Richard C. , Lewis Austin J. , Whittemore Colin T.
Published: October 2011

The purpose of the present review is to highlight some of the challenges and issues in developing nutritional guidelines for companion animals, and to provide some insights that may influence their future direction. For this purpose, we have chosen to provide a brief historical review of the development of dog and cat nutrient guidelines, and an analysis of current recommendations and of key institutions and bodies (notably the National Research Council) that are influential in defining nutrient guidelines for companion animals. In addition, we have also included a review of current approaches for defining nutritional guidelines for humans and farm animal livestock, as they provide differing perspectives and insights that may be instructive for the future development of nutritional guidelines for companion animals.
Haematology and plasma chemistry of the red top ice blue mbuna cichlid (Metriaclima greshakei)
Authors: Snellgrove Donna L. , Alexander Lucille G.
Published: October 2011

Clinical haematology and blood plasma chemistry can be used as a valuable tool to provide substantial diagnostic information for fish. A wide range of parameters can be used to assess nutritional status, digestive function, disease identification, routine metabolic levels, general physiological status and even the assessment and management of wild fish populations. However to evaluate such data accurately, baseline reference intervals for each measurable parameter must be established for the species of fish in question. Baseline data for ornamental fish species are limited, as research is more commonly conducted using commercially cultured fish. Blood samples were collected from sixteen red top ice blue cichlids (Metriaclima greshakei), an ornamental freshwater fish, to describe a range of haematology and plasma chemistry parameters. Since this cichlid is fairly large in comparison with most tropical ornamental fish, two independent blood samples were taken to assess a large range of parameters. No significant differences were noted between sample periods for any parameter. Values obtained for a large number of parameters were similar to those established for other closely related fish species such as tilapia (Oreochromisspp.). In addition to reporting the first set of blood values forM. Greshakei, to our knowledge, this study highlights the possibility of using previously established data for cultured cichlid species in studies with ornamental cichlid fish.
Intraruminal administration ofMegasphaera elsdeniimodulated rumen fermentation profile in mid-lactation dairy cows
Authors: Zebeli Qendrim , Terrill Sarah J , Mazzolari Alberto , Dunn Suzanna M , Yang Wen Z , Ametaj Burim N
Published: October 2011

This study evaluated the effects of intraruminal administration ofMegasphaera elsdeniion ruminal fermentation patterns, the profile of plasma metabolites, and milk yield and composition of mid-lactation dairy cows. Eight primiparous, ruminally cannulated Holstein cows were arranged in a paired 2×2 crossover design. Cows were randomly assigned to one of two treatments: 1) intraruminal inoculation of 35 ml suspension per day ofM. elsdeniiATCC 25940 (MEGA), containing 108cfu/ml of bacteria, dissolved in 35 ml of saline (0·15m), or 2) carrier alone (35 ml saline; CTR). Both postprandial and preprandial rumen volatile fatty acids (VFA) and plasma metabolite measurements were analysed. Postprandial VFA patterns were affected the most, with butyrate (P<0·01) and valerate (P<0·01) proportions increasing, and acetate (P<0·01), isobutyrate (P=0·05) and isovalerate (P<0·01) decreasing in MEGA cows. Preprandial data measured at various days showed that MEGA dosage tended to increase the molar proportion of propionate (P=0·09) and lower the acetate to propionate ratio (P=0·07) in the rumen fluid. There was no effect of treatment on rumen pH and on the concentration of lactate in the rumen as well as on selected preprandial plasma metabolites. Postprandial plasma concentrations of cholesterol tended to increase (P=0·07) in MEGA cows compared with CTR. Concentrations of non-esterified fatty acids (NEFA) in the plasma were lower in MEGA cows after the morning feeding (P<0·01). Sampling hour also affected plasma NEFA in this study. Plasma β-hydroxybutyrate (BHBA) were not affected by the treatment (P>0·05); however, after the morning feeding BHBA concentration was increased in both groups of cows. Dry matter intake and milk yield and composition were not affected by treatment. In conclusion, results indicate thatM. elsdeniihas the potential to modulate the rumen fermentation profile in mid-lactation Holstein cows, but these effects were only slightly reflected in changes in plasma metabolites and milk composition.
Oral cavity squamous cell carcinoma metastasis to the submandibular gland
Authors: Naidu T K , Naidoo S K , Ramdial P K
Published: October 2011

Introduction:

This study aimed to evaluate the incidence of submandibular gland metastases in cases of oral cavity squamous cell carcinoma.

Methods:

Sixty-nine patients treated between 1 January 2004 and 30 June 2009 were retrospectively reviewed. Patients were treated with wide local excision of the primary tumour, plus simultaneous neck dissection and reconstruction if required.

Results:

Of 69 submandibular glands from 46 men and 23 women (mean age, 58 years), 43 (62.3 per cent) had advanced, tumour stage three or four lesions. Histopathological reappraisal of all submandibular glands demonstrated an absence of metastatic spread. Only 2/69 (2.9 per cent) submandibular glands demonstrated ipsilateral contiguous tumour involvement.

Conclusion:

This study demonstrated an absence of metastasis to the submandibular gland from oral cavity squamous cell carcinoma. Patients with early stage oral cavity squamous cell carcinoma and with a pre-operative node stage zero neck may be candidates for preservation of the submandibular gland during neck dissection.
Multinodular thyroid goitre causing obstructive sleep apnoea syndrome
Authors: Gutierrez T , Leong A C , Pang L , Chevretton E , Jeannon J-P , Simo R
Published: October 2011

Background:

Obstructive sleep apnoea syndrome has been linked to obesity, nasal obstruction and adenotonsillar hypertrophy, but rarely to large thyroid goitres.

Objective:

To study the possible association between multinodular retrolaryngo-pharyngeal or retrosternal goitres and obstructive sleep apnoea syndrome.

Subjects and methods:

Retrospective case series at a tertiary referral centre (2000–2010). Study parameters included body mass index, Epworth sleep score and polysomnographic index.

Results:

Five patients were diagnosed with obstructive sleep apnoea syndrome and managed with nasal continuous positive airway pressure ventilation. Computed tomography showed a retrolaryngo-pharyngeal or retrosternal goitre with significant tracheal compression, displacement and laryngeal oedema. After total thyroidectomy, obstructive sleep apnoea resolved in all patients.

Conclusion:

Large, multinodular goitres with retrolaryngo-pharyngeal extension can cause obstructive sleep apnoea syndrome due to laryngeal compression and oedema. In such cases, total thyroidectomy enables resolution of symptoms. Patients with obstructive sleep apnoea syndrome should be screened for thyroid goitre.
Social and linguistic input in low-income African American mother–child dyads from 1 month through 2 years: Relations to vocabulary development
Authors: SHIMPI PRIYA M. , FEDEWA ALICIA , HANS SYDNEY
Published: October 2011

The relation of social and linguistic input measures to early vocabulary development was examined in 30 low-income African American mother–infant pairs. Observations were conducted when the child was 0 years, 1 month (0;1), 0;4, 0;8, 1;0, 1;6, and 2;0. Maternal input was coded for word types and tokens, contingent responsiveness, and directiveness. Children's outcome measures included productive vocabulary at 1;6 and 2;0. Patterns of social and linguistic input were highly consistent over time. Significant positive relations were found between linguistic input measures and child vocabulary development. Findings for social input measures included positive relations between directive input and child word types, which differs from previous research with European American middle-class samples.
The role of language skills in learning to read: The case of bilingualism in French overseas departments
Authors: NEGRO ISABELLE , GENELOT SOPHIE
Published: October 2011

This study aims to explain how the practice of two languages (French and Creole) in French overseas departments affects the first educational competencies acquired by children. The students’ performance in both languages was investigated at the beginning of kindergarten, and their reading capacities were measured at the end of Grade 1. The data analysis shows that the practice of Creole has no negative impact on success at reading in French. Furthermore, it appears that the students who performed the best in reading were those who were either more competent in French than in Creole, or those who were equally competent in both languages, according to their assessed reading competence. Thus, also discussed is the necessity of early exposure to a language's written code and the contribution that bilingualism makes to learning processes of reading.