bluuebunny/crossref_metadata_2025 huggingface dataset:
Inactivation of Polyphenoloxidase of Pear by Pulsed Electric Fields
Authors: Zhao Wei , Yang Ruijin , Hua Xiao , Zhang Wenbin , Tang Yali , Chen Tuo
Published: May 2010

Pulsed electric fields (PEF) were utilized for inhibition of polyphenoloxidase (PPO) of pear. The effects of PEF electric field strength, treatment time and the temperature on the reduction of PPO activity were evaluated in this study. A maximum of 95.5% inactivation of pear PPO was observed with the PEF treatment at 35 kV/cm for 1200 ?s at 40°C. The classical first-order inactivation as well as modified Hülshegers kinetic model adequately described the enzymatic inhibition in PEF processing. The second-order polynomial equation was a suitable model to analyze the inactivation of PPO using PEF technology since the PEF parameters such as PEF electric field strength, treatment time and temperature could be involved in this model.
Reliable prediction of heat of vaporization of n-alkanes at 298.15 K
Authors: Jovanovic Jovan , Grozdanic Dusan
Published: June 2010

A reliable model for the prediction of the heat of vaporization for n-alkanes at 298.15 K with the number of carbon atoms and normal boiling point as the only input parameters is recommended. The new model is compared with other literature models and was found to give the best results with absolute mean percentage deviation of 0.81 % and maximum absolute percentage deviation of 2.93 %.
The Efficacy of a Repeated Buccal Infiltration of Articaine in Prolonging Duration of Pulpal Anesthesia in the Mandibular First Molar
Authors: Pabst Lindsay , Nusstein John , Drum Melissa , Reader Al , Beck Mike
Published: June 2010

Previous studies have shown declining rates of pulpal anesthesia over 60 minutes when a cartridge of 4% articaine is used with 1∶100,000 epinephrine for buccal infiltration in the mandibular first molar. The authors conducted a prospective, randomized, single-blind, crossover study comparing the degree of pulpal anesthesia obtained with 2 sets of mandibular first molar buccal infiltrations, given in 2 separate appointments, to 86 adult subjects: an initial infiltration of a cartridge of 4% articaine with 1∶100,000 epinephrine plus a repeated infiltration of the same anesthetic and dose given 25 minutes following the initial infiltration versus an initial infiltration of a cartridge of 4% articaine with 1∶100,000 epinephrine plus a mock repeated infiltration given 25 minutes following the initial infiltration. The authors used an electric pulp tester to test the first molar for anesthesia in 3-minute cycles for 112 minutes after the injections. The repeated infiltration significantly improved pulpal anesthesia from 28 minutes through 109 minutes in the mandibular first molar. A repeated infiltration of a cartridge of 4% articaine with 1∶100,000 epinephrine given 25 minutes after an initial infiltration of the same type and dose of anesthetic significantly improved the duration of pulpal anesthesia, when compared with only an initial buccal infiltration, in the mandibular first molar.
Evaluation of the relationship between lesions in the gastroduodenal region and cyclooxygenase expression in clinically normal dogs
Authors: Wooten Jenna G. , Lascelles B. Duncan X. , Cook Vanessa L. , Law J. Mac , Blikslager Anthony T.
Published: June 2010

Objective—To determine whether clinically normal dogs have lesions in the pylorus and duodenum and to examine the expression of cyclooxygenase (COX) isoforms in the pylorus and duodenum of these dogs.

Animals—27 clinically normal dogs.

Procedures—Physical examination was performed on clinically normal dogs from animal shelters and research projects; the dogs were then euthanized. After the dogs were euthanized, the pylorus and duodenum were photographed and scored for gross appearance of lesions. Samples were obtained for histologic evaluation and determination of COX expression via western blot analyses. Tissues from the pylorus and duodenum were categorized as normal, inflamed, or eroded on the basis of histologic analysis. Each histologic category of tissue was then evaluated to determine the correlation with gross appearance and COX expression.

Results—Of the 27 dogs, 5 had unremarkable histologic findings in the pylorus and duodenum. Inflammation was found in the pylorus of 10 dogs and in the duodenum of 5 dogs. Epithelial erosion was detected in the pylorus of 1 dog and in the duodenum of 3 dogs. Gross appearance was not significantly correlated with histologic appearance. Expression of COX-1 was not upregulated by inflammation, whereas COX-2 expression was increased by inflammation or erosion.

Conclusions and Clinical Relevance—Dogs that appear to be clinically normal may have underlying gastroduodenal lesions associated with upregulation of COX-2. Because of the inability to determine this during routine physical examination, practitioners should be aware of this potential situation when prescribing COX inhibitors.
Evaluation of the effects of small interfering RNAs on in vitro replication of feline herpesvirus-1
Authors: Wilkes Rebecca P. , Kania Stephen A.
Published: June 2010

Objective—To evaluate the ability of 5 small interfering RNAs (siRNAs) targeting mRNA of the feline herpesvirus-1 (FHV-1) DNA polymerase gene to reduce in vitro viral replication and gene expression of FHV-1, to evaluate combinations of these siRNAs with siRNAs that target the glycoprotein D gene of FHV-1, and to determine the combination or combinations of siRNAs that yield the greatest inhibition of in vitro viral replication.

Sample Population—Cultured Crandell-Rees feline kidney (CRFK) cells.

Procedures—CRFK cells were transfected with siRNAs designed to target mRNA of the FHV-1 DNA polymerase gene. Effective treatment was determined by quantification of the inhibition of mRNA available for DNA polymerase translation, viral protein production, and viral replication. Combinations of 2 siRNAs that target mRNA of the FHV-1 DNA polymerase gene and 2 siRNAs that target the mRNA of the essential FHV-1 glycoprotein D gene were evaluated for the ability to inhibit viral replication.

Results—Verified by a reduction in viral gene expression, 2 of the 5 siRNAs designed to target mRNA of the FHV-1 DNA polymerase gene significantly suppressed viral replication. Two combinations of siRNAs that target mRNA of the FHV-1 DNA polymerase gene, the FHV-1 glycoprotein D gene, or both also significantly suppressed viral replication.

Conclusions and Clinical Relevance—Combinations of siRNAs that target mRNA of the FHV-1 DNA polymerase gene, FHV-1 glycoprotein D gene, or both could potentially be used as a treatment for the prevention of clinical disease associated with FHV-1 infection.
Experimental induction of recurrent airway obstruction with inhaled fungal spores, lipopolysaccharide, and silica microspheres in horses
Authors: Beeler-Marfisi Janet , Clark Mary Ellen , Wen Xin , Sears William , Huber Leslie , Ackerley Cameron , Viel Laurent , Bienzle Dorothee
Published: June 2010

Objective—To evaluate experimental induction of recurrent airway obstruction (RAO) with inhaled fungal spores, lipopolysaccharide, and silica microspheres in horses.

Animals—7 horses with and 3 horses without a history of RAO.

Procedures—RAO-susceptible horses ranged in age from 17 to approximately 30 years, and control horses ranged in age from 7 to approximately 15 years. Pure mold cultures were derived from repeated culture of hay and identified via gene amplification and sequencing. Pulmonary function testing and bronchoalveolar lavage were performed before and after nebulization with a suspension of spores derived from 3 fungi, lipopolysaccharide, and 1-μm silica microspheres in all horses. This was followed by a 4-month washout period and a further pulmonary function test followed by saline (0.9% NaCl) solution challenge and bronchoalveolar lavage.

Results—Lichtheimia corymbifera, Aspergillus fumigatus, and Eurotium amstelodami were consistently identified in cultures of moldy hay. Nebulization with fungal spores, lipopolysaccharide, and microspheres induced significant increases in pleural pressure in RAO-susceptible but not control horses. Airway neutrophilia developed in both groups of horses with exposure to challenge material but more severely in RAO-susceptible horses.

Conclusions and Clinical Relevance—Results indicated that inhalation of fungal spores in combination with lipopolysaccharide and silica microspheres can induce disease exacerbation in susceptible horses and may thus be a useful model for future standardized studies of RAO in horses.
Comparison of urine protein-to-creatinine ratio in urine samples collected by cystocentesis versus free catch in dogs
Authors: Beatrice Laura , Nizi Francesca , Callegari Daniela , Paltrinieri Saverio , Zini Eric , D'Ippolito Paola , Zatelli Andrea
Published: June 2010

Objective—To assess whether urine protein-to-creatinine (UPC) ratios determined in urine samples collected by cystocentesis versus those collected by free catch provide similar diagnostic information for dogs.

Design—Evaluation study.

Animals—115 client-owned dogs evaluated because of various health problems requiring urinalysis or to screen for proteinuria in an area endemic for leishmaniasis.

Procedures—230 paired urine samples, 1 collected by cystocentesis and 1 by free catch, were collected from the 115 dogs. The UPC ratio was determined in paired urine samples (n = 162) from 81 dogs with no indication of active inflammation according to urine sediment analysis. On the basis of the UPC ratio of urine sample collected by cystocentesis, dogs were classified as nonproteinuric (UPC ratio < 0.2), borderline proteinuric (UPC ratio of 0.2 to 0.5), or proteinuric (UPC ratio > 0.5), according to the International Renal Interest Society (IRIS).

Results—The correlation between UPC ratio in urine samples collected by cystocentesis and by free catch was strong (r2 = 0.90); 75 of 81 (92.6%) dogs had UPC ratios from both urine samples that resulted in classification in the same IRIS substage with a kappa coefficient of 0.83.

Conclusions and Clinical Relevance—The UPC ratio in dogs was minimally affected in urine samples collected by free catch, thus allowing correct grading of proteinuria with this method. The high reliability of the UPC ratio in free-catch urine samples coupled with the ease of collection should increase the use of this value for assessment of proteinuria.
QSPR modelling of normal boiling points and octanol/water partition coefficient for acyclic and cyclic hydrocarbons using SMILES-based optimal descriptors
Authors: Toropov A.A. , Toropova A.P. , Benfenati E.
Published: June 2010

Predictive quantitative structure - property relationships (QSPR) have been established for normal boiling points and octanol/water partition coefficient for acyclic and cyclic hydrocarbons using optimal descriptors calculated with simplified molecular input line entry system (SMILES). The probabilistic criteria for a rational definition of the domain of applicability of these models are discussed.
Effect of the polymeric coating over Fe3O4 particles used for magnetic separation
Authors: Reza Raúl , Martínez Pérez Carlos , Rodríguez González Claudia , Romero Humberto , García Casillas Perla
Published: June 2010

In this work, the synthesis of magnetite nanoparticles by two variant chemical coprecipitation methods that involve reflux and aging conditions was investigated. The influence of the synthesis conditions on particle size, morphology, magnetic properties and protein adsorption were studied. The synthesized magnetite nanoparticles showed a spherical shape with an average particle size directly influenced by the synthesis technique. Particles of average size 27 nm and 200 nm were obtained. When the coprecipitation method was used without reflux and aging, the smallest particles were obtained. Magnetite nanoparticles obtained from both methods exhibited a superparamagnetic behavior and their saturation magnetization was particle size dependent. Values of 67 and 78 emu g−1 were obtained for the 27 nm and 200 nm magnetite particles, respectively. The nanoparticles were coated with silica, aminosilane, and silica-aminosilane shell. The influence of the coating on protein absorption was studied using Bovine Serum Albumin (BSA) protein.
Investigation of unmatured hematopoietic cell migration in a mouse model
Authors: Biziulevičienė Gene , Kašėta Vytautas , Ramanauskaitė Giedrė , Vaitkuvienė Aida
Published: June 2010

The objective of this work was to examine the migration of transplanted bone marrow hematopoietic lin− cell population using the BALB/c mouse contact hypersensitivity model in vivo and to determine the time point at which they reach the site of injury (paw edema) as well as other undamaged organs, such as liver and spleen. Female BALB/c mice with induced contact hypersensitivity reaction were intravenously injected with 1×106 cells/mouse lin− cells, labeled with PKH67. The presence of lin− stained cells in mouse tissue sections was evaluated by fluorescent microscopy. After one hour, the labeled cells were found in mice paw edema and liver, and after 4 hours in spleen tissue. Migrated hematopoietic lin− cells remained in liver tissue for 48 h, and in spleen and paw edema at least for 72 h. Migrated stained cells in untreated paw were not found. The results prove that bone marrow unmatured hematopoietic cells are first found in paw edema, where they participate in the inhibition of tissue inflammation; these cells subsequently migrate to the liver and are found in the spleen shortly afterwards.
Antioxidant and antimicrobial properties of the lichens Anaptychya ciliaris, Nephroma parile, Ochrolechia tartarea and Parmelia centrifuga
Authors: Ranković Branislav , Ranković Darko , Kosanić Marijana , Marić Danijela
Published: June 2010

The aim of this study was to characterize the antioxidant and antimicrobial activity of the methanol extracts of: Anaptychya ciliaris, Nephroma parile, Ochrolechia tartarea and Parmelia centrifuga. The methanol extract of the P. centrifuga showed a strong antioxidant activity, in comparison to the extracts from A. ciliaris, O. tartarea and N. parile which were relatively weaker. Furthermore, the methanol extract of the lichen P. centrifuga was shown to contain the highest total phenol content (54.19 mg/g of the dry extract). Interestingly, a statistically significant positive relationship between the antioxidant activity and the total phenol content was observed. The minimum inhibitory concentration (MIC) against six bacterial and eleven fungi was established for the methanol extracts from each of species of lichens. The methanol extracts of the lichens P. centrifuga and O. tartarea showed the strongest both antibacterial and antifungal activity. Taken together, the results from this study suggest that the lichens P. centrifuga and O. tartarea may be used as a natural source of antioxidants in addition to providing certain antimicrobial features.
Antibacterial activity of oleanolic and ursolic acids and their derivatives
Authors: Wolska Krystyna , Grudniak Anna , Fiecek Beata , Kraczkiewicz-Dowjat Anna , Kurek Anna
Published: June 2010

Bacterial resistance to antibiotics is increasing at an alarming rate and many commonly used antibiotics are no longer effective. Thus, there is considerable interest in investigating novel antibacterial compounds, such as the plant-derived pentacyclic triterpenoids, including oleanolic acid (OA), ursolic acid (UA) and their derivatives. These compounds can be isolated from many medicinal and crop plants and their antibacterial, antiviral, antiulcer and anti-inflammatory effects are well documented. OA and UA are active against many bacterial species, particularly Gram-positive species, including mycobacteria. They inhibit bacterial growth and survival, and the spectrum of minimal inhibitory concentration (MIC) values is very broad. In addition, OA, UA and their derivatives display potent antimutagenic activity. Studies to identify the cellular targets and molecular mechanisms of OA and UA action were initiated a few years ago and it has already been demonstrated that both acids influence bacterial gene expression, the formation and maintenance of biofilms, cell autolysis and peptidoglycan turnover. Before these compounds can be used clinically as antimicrobial agents, further extensive studies are required to determine their cytotoxicity and the optimum mode of their application.
Genotoxicity of barley stripe mosaic virus in infected host plants
Authors: Andronic Larisa , Jacota Anatol , Bujoreanu Valeriu , Grigorov Tatyana
Published: June 2010

A comparative study of the effect of barley stripe mosaic virus (BSMV) and gamma irradiation on mitotic divisions in barley (Hordeum vulgare L.) roots was performed by evaluating the mitotic index (MI), micronucleus (MN) frequency and sister chromatid exchanges (SCE). Results indicate that, similarly to gamma irradiation at doses of 100, 150 and 250 Gy, BSMV reduces the mitotic activity, increases the micronucleus frequency and the rate of SCE and promotes the formation of C-metaphases. In root meristematic cells of the three barley cultivars studied (Galactic, Sonor and Unirea), the mitotic index of infected plants was found to be 52.5, 54.48 and 64.17%, respectively, lower than the uninfected control. An increase in frequency of sister chromatid exchanges was observed in all the experimental variants. In treatments involving viral infection alone or in combination with gamma irradiation chromosomes with three and more chromatid exchanges were observed, while their percentage in the control or in treatments with gamma irradiation alone was reduced. The results of the study indicate that in plants derived from irradiated seeds, BSMV produces an effect that is correlated nonlinearly with the radiation dose applied. Cytological analysis of mitotic divisions in barley roots revealed the genotoxicity of BSMV infection.
The contents of risk elements, arsenic speciation, and possible interactions of elements and betalains in beetroot (Beta vulgaris, L.) growing in contaminated soil
Authors: Száková Jiřina , Havlík Jaroslav , Valterová Barbora , Tlustoš Pavel , Goessler Walter
Published: June 2010

The effect of enhanced soil risk element contents on the uptake of As, Cd, Pb, and Zn was determined in two pot experiments. Simultaneously, transformation of arsenic and its compounds in beetroot (Beta vulgaris L.) plants was investigated. The mobile fractions of elements were determined in 0.05 mol L−1 (NH4)2SO4 extracts and did not exceed 2% of total soil arsenic, 9% of total cadmium, 3% of total lead, and 8% of total zinc, respectively. Although the soils were extremely contaminated the mobile portions of the elements represented only a small fragment of the total element content. Arsenic contents in beet plants reached up to 25 mg As kg−1 in roots and 48 mg As kg−1 in leaves in the soil characterized by the highest mobile arsenic portion. Arsenic portions extractable with water and phosphate buffer from the beetroot samples did not show significant differences between the extraction agents but the extractability was affected by the arsenic concentration. Arsenic was almost quantitatively extractable from the samples with the lowest total arsenic concentration, whereas in the samples with the highest total arsenic concentration less than 25% was extractable. Arsenate was the dominant arsenic compound in the extracts (70% in phosphate buffer, 50% in water extracts). A small portion of dimethylarsinic acid, not exceeding 0.5%, was detected only in the sample growing in the soil with the highest arsenic concentration. The role of betalains (betanin, isobetanin, vulgaxanthin I and vulgaxanthin II) in transformation/detoxification of arsenic in plants was not confirmed in this experiment because the plants were able to grow in the contaminated soil without any symptoms of arsenic toxicity.
Constraints on the origin of gabbroic rocks from the Moldanubian-Moravian units boundary (Bohemian Massif, Czech Republic and Austria)
Authors: Ulrych Jaromír , Ackerman Lukáš , Kachlík Václav , Hegner Ernst , Balogh Kadosa , Langrová Anna , Luna Jan , Fediuk Ferry , Lang Miloš , Filip Jiří
Published: June 2010

Constraints on the origin of gabbroic rocks from the Moldanubian-Moravian units boundary (Bohemian Massif, Czech Republic and Austria)

Gabbroic bodies from the Moldanubian Monotonous Group (Maříž) and the Moravian Vratěnín Unit (other sites), often showing retrogressive recrystallization at their margins in the amphibolite-facies grade, have norite, gabbronorite, gabbro and hornblendite compositions. Gabbros with preserved coronitic textures are limited to the Vratěnín Unit. The estimated equilibration temperatures derived from plagioclase-amphibole pairs and orthopyroxene Ca contents calculated for pressures 5-10 kbar overlap for coronitic (700-840 °C) and non-coronitic gabbroic rocks (680-850 °C). Although the Moldanubian (Maříž) gabbroic rocks are more Mg-rich compared to the Moravian gabbroids, they show crust-like La/Nb ratios of 2.1-6.6 characteristic of subduction-related magmatic rocks coupled with uniform low εNdvalues of + 0.6 to + 0.7. Apparent subduction-related features are probably caused by contamination by juvenile crust and/or by metamorphic fluid rich in incompatible elements during the Variscan metamorphism. Samples from Korolupy-Nonndorf and Mešovice have La/Nb ratios < 1.7 and show negative correlations between La/Nb and εNd. Such decoupling between La/Nb and εNdcould be attributed to contamination of the subduction-related parent magma by crustal material with higher La/Nb and lower εNdvalues. Samples from Uherčice show ambiguous geochemical patterns inherited from contamination by very old recycled material. Gabbroic rocks from Maříž should represent an underplated, partly layered cumulate body of continental tholeiite composition, strongly influenced by crustal contamination. In contrast, gabbroic bodies from the Vratěnín Unit, having a close spatial relationship to the surrounding garnet amphibolites, were emplaced into a lithologically variable passive margin sequence probably during the Cadomian extension.
An Early Miocene biserial foraminiferal event in the Transylvanian Basin (Romania)
Authors: Beldean Claudia , Filipescu Sorin , Bălc Ramona
Published: June 2010

An Early Miocene biserial foraminiferal event in the Transylvanian Basin (Romania)

Investigations of the Lower Miocene of the Transylvanian Basin reveal particularly high abundances (> 90 % of total foraminifera) of small sized biserial foraminifera (Bolivina/Streptochilus). This biotic event has not been noticed in the Transylvanian Basin so far probably owing to the facies misinterpretation and the small size of the specimens. SEM investigations allow more precise identification of biserial planktonic taxa and more accurate taxonomic interpretations. The high abundance ofBolivina/Streptochilusassemblages provide evidence for paleogeographic connections to the Indo-Pacific area and support new paleoenvironmental interpretations at the transition from the Early to Middle Miocene in relation to the paleoceanographic events. Both planktonic foraminifera and calcareous nannoplankton suggest a late Burdigalian age. A newBolivina/StreptochilusAbundance Biozone is proposed just below the Early/Middle Miocene boundary.
Devonian in Turkey — a review
Authors: Yalçin M. , Yilmaz Isak
Published: June 2010

Devonian in Turkey — a review

The Devonian Period is represented in Turkey by almost complete non-metamorphic sections of more than 1000 meters, which exhibit varying lithofacial associations. They are parts of thick Paleozoic sedimentary successions in the Pontides, Taurides and Arabian Plate. The tectonic setting and the paleogeographical origin of these terranes is different. Therefore, the litho- and biostratigraphy and facies characteristics of these Devonian successions would enable a comparison and a paleogeographical assignment of these tectono-stratigraphic units. Devonian successions of the Arabian Plate and of the Taurides are represented by facies associations ranging from tidal flat to a deep shelf. Whereas, those of the Istanbul and Çamdağ-Zonguldak areas in the Pontides by a deepening upward sequence from a shallow shelf into a basin and a stable shelf, respectively. The Devonian of the Arabian Plate and the Taurides can surely be assigned to Gondwana. A Peri-Gondwanan (Avalonian) setting is suggested for the paleogeographic position of the Devonian of the Pontides.
Chemical Experiments with Superheavy Elements
Authors: Türler Andreas
Published: June 2010

Unnoticed by many chemists, the Periodic Table of the Elements has been extended significantly in the last couple of years and the 7th period has very recently been completed with eka-Rn (element 118) currently being the heaviest element whose synthesis has been reported. These 'superheavy'
elements (also called transactinides with atomic number ? 104 (Rf)) have been artificially synthesized in fusion reactions at accelerators in minute quantities of a few single atoms. In addition, all isotopes of the transactinide elements are radioactive and decay with rather short half-lives.
Nevertheless, it has been possible in some cases to investigate experimentally chemical properties of transactinide elements and even synthesize simple compounds. The experimental investigation of superheavy elements is especially intriguing, since theoretical calculations predict significant
deviations from periodic trends due to the influence of strong relativistic effects. In this contribution first experiments with hassium (Hs, atomic number 108), copernicium (Cn, atomic number 112) and element 114 (eka-Pb) are reviewed.
Recent Biomimetic and Organocatalytic Syntheses of ?-Tocopherol
Authors: Chougnet Antoinette , Liu Kegang , Woggon Wolf-D.
Published: June 2010

We report here on our efforts to develop new strategies for the synthesis of ?-tocopherol, the biologically most significant member of the vitamin E family. This review comprises five new methods to generate the chiral chromane of ?-tocopherol with overall up to 29% yield
from commercially available material and up to 94% de.
Surgery for catastrophic epilepsy in infants 6 months of age and younger
Authors: Gowda Shaila , Salazar Fortino , Bingaman William E. , Kotagal Prakash , Lachhwani Deepak L. , Gupta Ajay , Davis Stephen , Niezgoda Julie , Wyllie Elaine
Published: June 2010

Object

Few data are available concerning efficacy and safety of surgery for catastrophic epilepsy in the first 6 months of life.

Methods

The authors retrospectively analyzed epilepsy surgeries in 15 infants ranging in age from 1.5 to 6 months (median 4 months) and weight from 4 to 10 kg (median 7 kg) who underwent anatomical (4 patients) or functional (7 patients) hemispherectomy, or frontal (1 patient), frontoparietal (2 patients), or parietooccipital (1 patient) resection for life-threatening catastrophic epilepsy due to malformation of cortical development.

Results

No patient died. Intraoperative complications included an acute ischemic infarction with hemiparesis in our youngest, smallest infant. The most frequent complication was blood loss requiring transfusion, which was encountered in every case. The estimated blood loss was 3–214% (median 63%) of the total blood volume. At maximum follow-up of 6–121 months (median 60 months), 46% were seizure free.

Conclusions

Epilepsy surgery may be effective in young infants as it is in older children. However, intraoperative blood loss and risk of permanent postoperative neurological deficits present significant challenges.
Transnasal odontoid resection followed by posterior decompression and occipitocervical fusion in children with Chiari malformation Type I and ventral brainstem compression
Authors: Hankinson Todd C. , Grunstein Eli , Gardner Paul , Spinks Theodore J. , Anderson Richard C. E.
Published: June 2010

Object

In rare cases, children with a Chiari malformation Type I (CM-I) suffer from concomitant, irreducible, ventral brainstem compression that may result in cranial neuropathies or brainstem dysfunction. In these circumstances, a 360° decompression supplemented by posterior stabilization and fusion is required. In this report, the authors present the first experience with using an endoscopic transnasal corridor to accomplish ventral decompression in children with CM-I that is complicated by ventral brainstem compression.

Methods

Two children presented with a combination of occipital headaches, swallowing dysfunction, myelopathy, and/or progressive scoliosis. Imaging studies demonstrated CM-I with severely retroflexed odontoid processes and ventral brainstem compression. Both patients underwent an endoscopic transnasal approach for ventral decompression, followed by posterior decompression, expansive duraplasty, and occipital-cervical fusion.

Results

In both patients the endoscopic transnasal approach provided excellent ventral access to decompress the brainstem. When compared with the transoral approach, endoscopic transnasal access presents 4 potential advantages: 1) excellent prevertebral exposure in patients with small oral cavities; 2) a surgical corridor located above the hard palate to decompress rostral pathological entities more easily; 3) avoidance of the oral trauma and edema that follows oral retractor placement; and 4) avoidance of splitting the soft or hard palate in patients with oral-palatal dysfunction from ventral brainstem compression.

Conclusions

The endoscopic transnasal approach is atraumatic to the oral cavity, and offers a more superior region of exposure when compared with the standard transoral approach. Depending on their comfort level with endoscopic surgical techniques, pediatric neurosurgeons should consider this approach in children with pathological entities requiring ventral brainstem decompression.
Lumbar lipomyelomeningocele and sacrococcygeal teratoma in siblings: support for an alternative theory of spinal teratoma formation
Authors: Oliveria Seth F. , Thompson Eric M. , Selden Nathan R.
Published: June 2010

Sacrococcygeal teratomas may arise in association with regional developmental errors affecting the caudal embryonic segments and may originate within lumbosacral lipomas. It is therefore possible that sacrococcygeal teratomas and lumbosacral lipomas represent related disorders of embryogenesis. Accordingly, the authors report the cases of 2 siblings. The first child (female) was born with a mature Altman Type III sacrococcygeal teratoma that was resected when she was a neonate. Subsequently, a younger brother was found soon after birth to have an L-4–level lipomyelomeningocele and underwent partial resection and spinal cord untethering at 4 months of age. Although familial forms of each of these conditions have been reported, this is, to the authors' knowledge, the first reported occurrence of lipomyelomeningocele and sacrococcygeal teratoma in siblings. They propose that an inherited regional tendency to developmental error affecting the caudal embryonic segments was shared by these siblings and resulted in spinal teratoma formation in one of them.
The temperature regime of Fimbulisen, Antarctica
Authors: Humbert Angelika
Published: June 2010

Numerical simulations of the temperature regime of the ice shelf Fimbulisen, Antarctica, are presented. A vertical temperature profile (S1) of Fimbulisen has been measured at the extension of Jutulstraumen, in which the temperature decreases with depth. The three-dimensional steady-state temperature field was computed by a finite-element technique. Horizontal flow velocities and surface accumulation rates were derived from observations. The basal melt rate distribution arose from an assumption of balance in the mass continuity equation. The computed basal melt rate distribution (ab) indicates that the highest basal melt rates, up to 15 m a 1 occur at the inflow gate of Jutulstraumen, and low basal melt rates (<0.6ma 1) occur in the slower moving parts. Where the ice shelf overhangs the continental shelf, ab ~1.2ma−1 . The resulting temperature field indicates that Fimbulisen consists of a cold middle part, built up by the extension of Jutulstraumen, and warmer ice masses in slow-moving areas to the west and east. Furthermore, model runs were set up in which the atmospheric temperatures increased in +1 K steps. The results suggest that the warming effectively increases the temperatures throughout the ice column in the slower-moving parts, therefore enhancing shear at the margins of the extension of Jutulstraumen.
Mapping the grounding zone of the Ross Ice Shelf, Antarctica, using ICESat laser altimetry
Authors: Brunt Kelly M. , Fricker Helen A. , Padman Laurie , Scambos Ted A. , O’Neel Shad
Published: June 2010

We use laser altimetry from the Ice, Cloud, and land Elevation Satellite (ICESat) to map the grounding zone (GZ) of the Ross Ice Shelf, Antarctica, at 491 locations where ICESat tracks cross the grounding line (GL). Ice flexure in the GZ occurs as the ice shelf responds to short-term sea-level changes due primarily to tides. ICESat repeat-track analysis can be used to detect this region of flexure since each repeated pass is acquired at a different tidal phase; the technique provides estimates for both the landward limit of flexure and the point where the ice becomes hydrostatically balanced. We find that the ICESat-derived landward limits of tidal flexure are, in many places, offset by several km (and up to ∼60km) from the GL mapped previously using other satellite methods. We discuss the reasons why different mapping methods lead to different GL estimates, including: instrument limitations; variability in the surface topographic structure of the GZ; and the presence of ice plains. We conclude that reliable and accurate mapping of the GL is most likely to be achieved when based on synthesis of several satellite datasets.
Modelled response of the volume and thickness of the Antarctic ice sheet to the advance of the grounded area
Authors: Saito Fuyuki , Abe-Ouchi Ayako
Published: June 2010

Numerical experiments are performed for the Antarctic ice sheet to study the sensitivity of the ice volume to variations in the area of grounded ice and to changes in the climate during the most recent deglaciation. The effect of the variations in the grounded area is found to be the major source of changes in the ice volume, while the effect of climate change was minor. The maximum possible contribution of the ice-volume change to sea-level rise during the deglaciation is estimated to be 36 m, which covers most values estimated in previous studies. The effect of the advance of the ice-sheet margin over those regions not connected to the major ice shelves contributes one-third of the total ice-volume change, which is comparable to the effect of the grounding of the Filchner–Ronne Ice Shelf and the contribution of the Ross and Amery Ice Shelves together.
Coral Ecosystem Resilience, Conservation and Management on the Reefs of Jamaica in the Face of Anthropogenic Activities and Climate Change
Authors: Crabbe M. James C.
Published: June 2010

Knowledge of factors that are important in reef resilience and integrity help us understand how reef ecosystems react following major anthropogenic and environmental disturbances. The North Jamaican fringing reefs have shown some recent resilience to acute disturbances from hurricanes and bleaching, in addition to the recurring chronic stressors of over-fishing and land development. Factors that can improve coral reef resilience are reviewed, and reef rugosity is shown to correlate with coral cover and growth, particularly for branching Acropora species. The biodiversity index for the Jamaican reefs was lowered after the 2005 mass bleaching event, as were the numbers of coral colonies, but both had recovered by 2009. The importance of coastal zone reef management strategies and the economic value of reefs are discussed, and a protocol is suggested for future management of Jamaican reefs.
A Differential Evolution-Based Routing Algorithm for Environmental Monitoring Wireless Sensor Networks
Authors: Li Xiaofang , Xu Lizhong , Wang Huibin , Song Jie , Yang Simon X.
Published: June 2010

The traditional Low Energy Adaptive Cluster Hierarchy (LEACH) routing protocol is a clustering-based protocol. The uneven selection of cluster heads results in premature death of cluster heads and premature blind nodes inside the clusters, thus reducing the overall lifetime of the network. With a full consideration of information on energy and distance distribution of neighboring nodes inside the clusters, this paper proposes a new routing algorithm based on differential evolution (DE) to improve the LEACH routing protocol. To meet the requirements of monitoring applications in outdoor environments such as the meteorological, hydrological and wetland ecological environments, the proposed algorithm uses the simple and fast search features of DE to optimize the multi-objective selection of cluster heads and prevent blind nodes for improved energy efficiency and system stability. Simulation results show that the proposed new LEACH routing algorithm has better performance, effectively extends the working lifetime of the system, and improves the quality of the wireless sensor networks.
Modeling of Current Consumption in 802.15.4/ZigBee Sensor Motes
Authors: Casilari Eduardo , Cano-García Jose M. , Campos-Garrido Gonzalo
Published: June 2010

Battery consumption is a key aspect in the performance of wireless sensor networks. One of the most promising technologies for this type of networks is 802.15.4/ZigBee. This paper presents an empirical characterization of battery consumption in commercial 802.15.4/ZigBee motes. This characterization is based on the measurement of the current that is drained from the power source under different 802.15.4 communication operations. The measurements permit the definition of an analytical model to predict the maximum, minimum and mean expected battery lifetime of a sensor networking application as a function of the sensor duty cycle and the size of the sensed data.
Consumers’ Sustainability Perceptions of the Supply Chain of Locally Produced Food
Authors: Paloviita Ari
Published: June 2010

This article is based on a qualitative focus group study regarding consumer perceptions about the sustainability of locally produced food supply chains. Sustainability perceptions were analyzed through thematic content analysis, where the most important economic, environmental and social themes of the supply chain were emphasized. According to the research findings, the socio-cultural aspects encompassing locally produced food form the most important sustainability dimension for consumers. Although the sample size is small, consisting of 19 consumers and limited to Central Finland, the findings suggest that the sustainability of local food should be promoted via socio-cultural arguments alongside economic or environmental ones. The results conclude that the development of local food networks requires direct personal relationships with producers, social networking, consumer education and communication.
The System Dynamics of Forest Cover in the Developing World: Researcher Versus Community Perspectives
Authors: Olabisi Laura Schmitt
Published: June 2010

Efforts to increase forest cover in the developing world will only succeed if the root causes of deforestation are addressed. Researchers designing reforestation initiatives tend to emphasize macro-level drivers of deforestation, about which they have extensive data and knowledge. On the other hand, local people have contextually based knowledge of forest cover dynamics in their region—about which external researchers may be largely ignorant. This type of perception gap between researchers and community members has led to many failed or insufficiently implemented projects. An emerging tool—group model-building with system dynamics—shows promise in its ability to integrate different perspectives on a complex problem such as forest cover loss. In this study, I use system dynamics modeling methodology to compare causal loop diagrams of forest cover dynamics on Negros Island, Philippines generated by researchers working for the World Wildlife Fund with causal loop diagrams generated by community members in upland Negros. The diagrams were significantly different, with very few variables in common, but both illuminate critical aspects of the deforestation problem on the island. I conclude that reforestation initiatives in the Philippines would benefit from incorporating all relevant information into a single, coherent model.
Toxins and Secretion Systems of Photorhabdus luminescens
Authors: Rodou Athina , Ankrah Dennis O. , Stathopoulos Christos
Published: June 2010

Photorhabdus luminescens is a nematode-symbiotic, gram negative, bioluminescent bacterium, belonging to the family of Enterobacteriaceae.Recent studies show the importance of this bacterium as an alternative source of insecticides, as well as an emerging human pathogen. Various toxins have been identified and characterized in this bacterium. These toxins are classified into four major groups: the toxin complexes (Tcs), the Photorhabdus insect related (Pir) proteins, the “makes caterpillars floppy” (Mcf) toxins and the Photorhabdus virulence cassettes (PVC); the mechanisms however of toxin secretion are not fully elucidated. Using bioinformatics analysis and comparison against the components of known secretion systems, multiple copies of components of all known secretion systems, except the ones composing a type IV secretion system, were identified throughout the entire genome of the bacterium. This indicates that Photorhabdus luminescens has all the necessary means for the secretion of virulence factors, thus it is capable of establishing a microbial infection.
Alpha-Tocopherol Counteracts the Cytotoxicity Induced by Ochratoxin A in Primary Porcine Fibroblasts
Authors: Fusi Eleonora , Rebucci Raffaella , Pecorini Chiara , Campagnoli Anna , Pinotti Luciano , Saccone Francesca , Cheli Federica , Purup Stig , Sejrsen Kristen , Baldi Antonella
Published: June 2010

The aims of the current study were to determine the half-lethal concentration of ochratoxin A (OTA) as well as the levels of lactate dehydrogenase release and DNA fragmentation induced by OTA in primary porcine fibroblasts, and to examine the role of α-tocopherol in counteracting its toxicity. Cells showed a dose-, time- and origin-dependent (ear vs. embryo) sensitivity to ochratoxin A. Pre-incubation for 3 h with 1 nM α-tocopherol significantly (P < 0.01) reduced OTA cytotoxicity, lactate dehydrogenase release and DNA damage in both fibroblast cultures. These findings indicate that α-tocopherol supplementation may counteract short-term OTA toxicity, supporting its defensive role in the cell membrane.
Differential Cell Sensitivity between OTA and LPS upon Releasing TNF-α
Authors: Al-Anati Lauy , Essid Ebtisam , Stenius Ulla , Beuerlein Knut , Schuh Klaus , Petzinger Ernst
Published: June 2010

The release of tumor necrosis factor α (TNF-α) by ochratoxin A (OTA) was studied in various macrophage and non-macrophage cell lines and compared with E. coli lipopolysaccharide (LPS) as a standard TNF-α release agent. Cells were exposed either to 0, 2.5 or 12.5 µmol/L OTA, or to 0.1 µg/mL LPS, for up to 24 h. OTA at 2.5 µmol/L and LPS at 0.1 µg/mL were not toxic to the tested cells as indicated by viability markers. TNF-a was detected in the incubated cell medium of rat Kupffer cells, peritoneal rat macrophages, and the mouse monocyte macrophage cell line J774A.1: TNF-a concentrations were 1,000 pg/mL, 1,560 pg/mL, and 650 pg/mL, respectively, for 2.5 µmol/L OTA exposure and 3,000 pg/mL, 2,600 pg/mL, and 2,115 pg/mL, respectively, for LPS exposure. Rat liver sinusoidal endothelial cells, rat hepatocytes, human HepG2 cells, and mouse L929 cells lacked any cytokine response to OTA, but showed a significant release of TNF-a after LPS exposure, with the exception of HepG2 cells. In non-responsive cell lines, OTA lacked both any activation of NF-κB or the translocation of activated NF-κB to the cell nucleus, i.e., in mouse L929 cells. In J774A.1 cells, OTA mediated TNF-a release via the pRaf/MEK 1/2–NF-κB and p38-NF-κB pathways, whereas LPS used pRaf/MEK 1/2-NF-κB, but not p38-NF-κB pathways. In contrast, in L929 cells, LPS used other pathways to activate NF-κB. Our data indicate that only macrophages and macrophage derived cells respond to OTA and are considered as sources for TNF-a release upon OTA exposure.
Deoxynivalenol-Induced Proinflammatory Gene Expression: Mechanisms and Pathological Sequelae
Authors: Pestka James J.
Published: June 2010

The trichothecene mycotoxin deoxynivalenol (DON) is commonly encountered in human cereal foods throughout the world as a result of infestation of grains in the field and in storage by the fungus Fusarium. Significant questions remain regarding the risks posed to humans from acute and chronic DON ingestion, and how to manage these risks without imperiling access to nutritionally important food commodities. Modulation of the innate immune system appears particularly critical to DON’s toxic effects. Specifically, DON induces activation of mitogen-activated protein kinases (MAPKs) in macrophages and monocytes, which mediate robust induction of proinflammatory gene expression—effects that can be recapitulated in intact animals. The initiating mechanisms for DON-induced ribotoxic stress response appear to involve the (1) activation of constitutive protein kinases on the damaged ribosome and (2) autophagy of the chaperone GRP78 with consequent activation of the ER stress response. Pathological sequelae resulting from chronic low dose exposure include anorexia, impaired weight gain, growth hormone dysregulation and aberrant IgA production whereas acute high dose exposure evokes gastroenteritis, emesis and a shock-like syndrome. Taken together, the capacity of DON to evoke ribotoxic stress in mononuclear phagocytes contributes significantly to its acute and chronic toxic effects in vivo. It is anticipated that these investigations will enable the identification of robust biomarkers of effect that will be applicable to epidemiological studies of the human health effects of this common mycotoxin.
Antiviral Treatment of Chronic Hepatitis B Virus (HBV) Infections
Authors: De Clercq Erik , Férir Geoffrey , Kaptein Suzanne , Neyts Johan
Published: June 2010

While 25 compounds have been formally licensed for the treatment of HIV infection (AIDS), only seven licensed products are currently available for the treatment of chronic hepatitis B virus (HBV) infection: interferon-α, pegylated interferon-α, lamivudine, adefovir (dipivoxil), entecavir, telbivudine and tenofovir (disoproxil fumarate). In contrast to the treatment of HIV infections where the individual drugs are routinely used in combination, for the treatment of chronic HBV infection the individual drugs are generally used in monotherapy. In principle, combination drug therapy should allow reducing the likelihood of drug-resistant development.
Synthesis, characterization and photoinduced curing of polysulfones with (meth)acrylate functionalities
Authors: Dizman Cemil , Ates Sahin , Torun Lokman , Yagci Yusuf
Published: June 2010

The UV-curable telechelic polysulfones with (meth)acrylate functionalities were synthesized by condensation polymerization and subsequent esterification. The final polymers and intermediates at various stages were characterized by 1H NMR, FT-ATR, and GPC. The oligomeric films prepared from the appropriate solutions containing these telechelics and 2,2-dimethoxy-2-phenylacetophenone (DMPA) as the photoinitiator undergo rapid polymerization upon irradiation forming insoluble networks. The photo-curing behavior was investigated by photo-DSC and the effects of the molecular weight of the polysulfone precursor and type of functionality on the rate of polymerization and conversion were evaluated. Thermal properties of the photochemically cured films were studied by differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA).