bluuebunny/crossref_metadata_2025 huggingface dataset:
Morphometric Investigations of the Connections between the Posterior C-1 Root and the Accessory Nerve in the Human Cranial Cervical Region
Authors: Schneider U. , Biörnsen A. , Hagenah R.
Published: July 2008

The anastomosis of the spinal section of the accessory nerve and the posterior C-1 root was examined in eight human corpses at the light-microscopical level by image analysis. The numbers of nerve fibers caudal and cranial to the anastomosis were compared. The morphometric data suggest that somatic efferent fibers of the spinal accessory nerve extend to proprioceptors in the sternocleidomastoideus and trapezius muscles.
Epithelial-Mesenchymal Transformations in Early Avian Heart Development
Authors: Markwald R. , Eisenberg C. , Eisenberg L. , Trusk T. , Sugi Y.
Published: July 2008

Cardiac morphogenesis proceeds from a sequential series of epithelial-mesenchymal transitions which begins by establishing bipotential heart-forming cells and later their segregation into endocardial and myocardial lineages. Cells within each lineage integrate to form two concentric epithelia which inductively interact to transform cells of the inner epithelium, the endocardium, into mesenchymal or ‘cushion’ cells. Noncardiogenic epithelia (dorsal mesocardium, epicardium, neural ectoderm and coelomic mesothelium) undergo transition into populations of extracardiac mesenchyme that combine over time with cushion tissue to remodel the simple tubular heart into a four-chambered organ. Model systems are described for studying the mechanisms of cardiac-related transformations including primary cultures of precardiac epithelia and a differentiation-inducible, avian stem cell line called QCE-6. Focus is centered on the molecular mechanism by which endocardial epithelium transforms into cushion mesenchyme. Experimental findings are reviewed and interpreted in the context of a hypothetical model that seeks to answer why only some cells within an epithelium transform and whether the transformation process is regulated by intrinsic or extrinsic mechanisms. The model proposes that epithelial cells competent to transform to mesenchyme express characteristic markers including receptors for extrinsic signals secreted by stimulator cells (e.g. myocardium). Candidate extrinsic signals include multicomponent complexes called adherons. If applied directly to cultured endocardium, myocardial adherons but not those secreted by L6 myoblasts, induce changes in gene expression within target endocardial cells for proteases and cellxell and celkmatrix adhesion molecules that accompanied transformation to mesenchyme. A main component of myocardial adherons has been identified as ES antigens, one of which, ES/130, has been cloned, found to have a novel sequence and in culture assays shown to be required for endocardium to transform to mesenchyme. The spatiotemporal pattern of ES protein expression within the embryo suggests that common mechanisms may exist for embryonic epithelial-mesenchymal transformations.
Intestinal Growth in Altricial European Starling (Sturnus vulgaris) and Precocial Japanese Quail (Coturnix coturnix japonica)
Authors: Starck J.M.
Published: July 2008

This paper introduces the comparison of altricial and precocial birds as a model system for the study of patterns of intestinal growth. It reports on comparative morphometric and cytokinetic studies of intestinal growth in altricial European starling (Sturnus vulgaris) and precocial Japanese quail (Coturnix coturnix japonica). Morphometric data of five gut segments of neonates and adults of both species are provided to evaluate the growth of the intestine. A double labelling technique combining 3H-thymidine autoradiography with 5-bromo-2’-deoxyuridine immunohistochemistry gives labelling index, length of S-phase, and tissue turnover time for hatchlings and adults of both species. The results of morphometry show a similar pattern of intestinal growth in both species, a strong dependency of intestinal growth on body size, and a clear topographic separation of areas of cell proliferation from the functional mucosal epithelium. The results of the cytokinetic experiments indicate a constant length of the S-phase independent of species, development, and age. The 3H-thymidine labelling index is significantly higher in neonate quail than in neonate starling. Between adult animals of both species, the labelling index does not differ significantly except for the duodenum which has a higher index in starling. The turnover time necessary to replace the mucosal epithelium is 3 days in hatchlings of both species and ranges between 10 and 17 days in adults. A diurnal pattern of cell proliferation, as previously reported in adult quail, is not present in neonate quail. Thus, differences in intestinal growth among altricial and precocial birds are primarily based on size differences of proliferation areas whilst cellular proliferation rates have only minor impact on intestinal growth. The short turnover time and the high rates of cell proliferation suggest that the intestine is a flexible organ that may be adjusted in size and function to the actual needs of the growing bird.
Progression of Cerebral Small Vessel Disease in Relation to Risk Factors and Cognitive Consequences
Authors: van Dijk Ewoud J. , Prins Niels D. , Vrooman Henri A. , Hofman Albert , Koudstaal Peter J. , Breteler Monique M.B.
Published: July 2008

Background and Purpose—

Cerebral white matter lesions and lacunar infarcts are small vessel disease-related lesions, which are associated with cognitive decline and dementia. We aimed to assess the relationship between risk factors, effect modifiers, and progression of these lesions. Furthermore, we studied the cognitive consequences of lesion progression.

Methods—

Six hundred sixty-eight people, aged 60 to 90 years, underwent repeated MRI scanning and neuropsychological testing within 3-year follow-up. We rated incident lacunar infarcts and change in periventricular and subcortical white matter lesion severity with a semiquantitative scale. We assessed the relationships between age, sex, baseline lesion load, risk factors, lesion progression, and change in cognitive function by multivariate regression analyses and additional stratified analyses.

Results—

Baseline lesion load, higher age, high blood pressure, and current smoking were independently associated with progression of white matter lesions. Women had more marked progression of subcortical white matter lesions and incident lacunar infarcts compared with men. Carotid atherosclerosis was associated with incident lacunar infarcts. Higher blood pressure did not contribute to lesion progression in people with already severe lesions at baseline nor in the very old. Lesion progression was associated with a paralleled decline in general cognitive function and in particular with a decreased information processing speed.

Conclusions—

Higher age, female sex, cigarette smoking, elevated blood pressure, and baseline lesion load were associated with small vessel disease progression. Age and baseline lesion load influenced the risk relations with blood pressure. Progression of small vessel disease was related to a paralleled decline in cognitive function.
Glutathione S‐Transferase A1 Genetic Variants Reduce Busulfan Clearance in Children Undergoing Hematopoietic Cell Transplantation
Authors: Johnson L'Aurelle , Orchard Paul J. , Baker K. Scott , Brundage Richard , Cao Qing , Wang Xinjing , Langer Erica , Maasah Sharein Farag‐El , Ross Julie A. , Remmel Rory , Jacobson Pamala A.
Published: July 2008

The effect of glutathione S‐transferase variants on pediatric busulfan metabolism was investigated by noncompartmental and population pharmacokinetic modeling. Twenty‐nine children who underwent related or unrelated bone marrow or umbilical cord blood hematopoietic cell transplant were retrospectively studied. GSTA1, GSTP1, and GSTM1 variants were explored for their effects on busulfan exposures. Noncompartmental pharmacokinetic analyses showed that carriers of GSTA1*B had a 2.6‐fold higher busulfan area under the curve and concentration at steady state compared with noncarriers (i>P< ≤ .01). Population pharmacokinetic modeling demonstrated that carriers of GSTA1*B reduced busulfan clearance by 30%. Monte Carlo simulations were then performed to assess busulfan dosing regimens based on GSTA1 genotypes. Simulations determined that dosing based on GSTA1 genotype, weight, and age resulted in fewer children exceeding the upper therapeutic limit compared with dosing using age and weight only. Larger, prospective studies are needed to confirm these findings.
Direct and Acute Cardiotoxic Effects of Ultrafine Air Pollutants in Spontaneously Hypertensive Rats and Wistar—Kyoto Rats
Authors: Hwang Hyosook , Kloner Robert A. , Kleinman Michael T. , Simkhovich Boris Z.
Published: July 2008

It is hypothesized that preexisting cardiovascular disease could affect the susceptibility to direct and acute cardiotoxic effects of ultrafine air pollutants. Ultrafine particles (UFP) isolated from 12.5 mg of diesel particulate matter (National Institute of Standards and Technology) were infused into isolated Langendorffperfused hearts obtained from spontaneously hypertensive rats (SHR) and normotensive control Wistar— Kyoto rats (WKY). Perfusion for 30 minutes with UFP reduced cardiac function in both groups—but to a greater extent in WKY. In SHR, developed pressure was reduced by 24.1 ± 4.4% of baseline and maximal d P/d t was reduced by 19.8 ± 4.9%; in WKY, developed pressure was reduced by 43.5 ± 7.3% and maximal d P/d t by 41.8 ± 8.2% ( P < .05 for maximal d P/d t in SHR vs WKY). Coronary flow was decreased by 30.3% versus 53.7% in SHR versus WKY ( P < .05). The results of this study suggest that although UFP depress myocardial contractile response and coronary flow in both SHR and WKY the underlying hypertension does not necessarily worsen the response.
Culture creates genetic structure in the Caucasus: Autosomal, mitochondrial, and Y-chromosomal variation in Daghestan
Authors: Marchani Elizabeth E , Watkins W Scott , Bulayeva Kazima , Harpending Henry C , Jorde Lynn B
Published: July 2008

Background

Near the junction of three major continents, the Caucasus region has been an important thoroughfare for human migration. While the Caucasus Mountains have diverted human traffic to the few lowland regions that provide a gateway from north to south between the Caspian and Black Seas, highland populations have been isolated by their remote geographic location and their practice of patrilocal endogamy. We investigate how these cultural and historical differences between highland and lowland populations have affected patterns of genetic diversity. We test 1) whether the highland practice of patrilocal endogamy has generated sex-specific population relationships, and 2) whether the history of migration and military conquest associated with the lowland populations has left Central Asian genes in the Caucasus, by comparing genetic diversity and pairwise population relationships between Daghestani populations and reference populations throughout Europe and Asia for autosomal, mitochondrial, and Y-chromosomal markers.

Results

We found that the highland Daghestani populations had contrasting histories for the mitochondrial DNA and Y-chromosome data sets. Y-chromosomal haplogroup diversity was reduced among highland Daghestani populations when compared to other populations and to highland Daghestani mitochondrial DNA haplogroup diversity. Lowland Daghestani populations showed Turkish and Central Asian affinities for both mitochondrial and Y-chromosomal data sets. Autosomal population histories are strongly correlated to the pattern observed for the mitochondrial DNA data set, while the correlation between the mitochondrial DNA and Y-chromosome distance matrices was weak and not significant.

Conclusion

The reduced Y-chromosomal diversity exhibited by highland Daghestani populations is consistent with genetic drift caused by patrilocal endogamy. Mitochondrial and Y-chromosomal phylogeographic comparisons indicate a common Near Eastern origin of highland populations. Lowland Daghestani populations show varying influence from Near Eastern and Central Asian populations.
Association study of polymorphisms in the neutral amino acid transporter genes SLC1A4, SLC1A5 and the glycine transporter genes SLC6A5, SLC6A9with schizophrenia
Authors: Deng Xiangdong , Sagata Noriaki , Takeuchi Naoko , Tanaka Masami , Ninomiya Hideaki , Iwata Nakao , Ozaki Norio , Shibata Hiroki , Fukumaki Yasuyuki
Published: July 2008

Background

Based on the glutamatergic dysfunction hypothesis for schizophrenia pathogenesis, we have been performing systematic association studies of schizophrenia with the genes involved in glutametergic transmission. We report here association studies of schizophrenia withSLC1A4,SLC1A5encoding neutral amino acid transporters ASCT1, ASCT2, andSLC6A5,SLC6A9encoding glycine transporters GLYT2, GLYT1, respectively.

Methods

We initially tested the association of 21 single nucleotide polymorphisms (SNPs) distributed in the four gene regions with schizophrenia using 100 Japanese cases-control pairs and examined allele, genotype and haplotype association with schizophrenia. The observed nominal significance were examined in the full-size samples (400 cases and 420 controls).

Results

We observed nominally significant single-marker associations with schizophrenia in SNP2 (P= 0.021) and SNP3 (P= 0.029) ofSLC1A4, SNP1 (P= 0.009) and SNP2 (P= 0.022) ofSLC6A5. We also observed nominally significant haplotype associations with schizophrenia in the combinations of SNP2-SNP7 (P= 0.037) ofSLC1A4and SNP1-SNP4 (P= 0.043) ofSLC6A5. We examined all of the nominal significance in the Full-size Sample Set, except one haplotype with insufficient LD. The significant association of SNP1 ofSLC6A5with schizophrenia was confirmed in the Full-size Sample Set (P= 0.018).

Conclusion

We concluded that at least one susceptibility locus for schizophrenia may be located within or nearbySLC6A5, whereasSLC1A4,SLC1A5andSLC6A9are unlikely to be major susceptibility genes for schizophrenia in the Japanese population.
The omega-3 fatty acid, eicosapentaenoic acid (EPA), prevents the damaging effects of tumour necrosis factor (TNF)-alpha during murine skeletal muscle cell differentiation
Authors: Magee Peter , Pearson Stephen , Allen Jeremy
Published: July 2008

Background

Eicosapentaenoic acid (EPA) is a ώ-3 polyunsaturated fatty acid with anti-inflammatory and anti-cachetic properties that may have potential benefits with regards to skeletal muscle atrophy conditions where inflammation is present. It is also reported that pathologic levels of the pro-inflammatory cytokine tumour necrosis factor (TNF)-α are associated with muscle wasting, exerted through inhibition of myogenic differentiation and enhanced apoptosis. These findings led us to hypothesize that EPA may have a protective effect against skeletal muscle damage induced by the actions of TNF-α.

Results

The deleterious effects of TNF-α on C2C12 myogenesis were completely inhibited by co-treatment with EPA. Thus, EPA prevented the TNF-mediated loss of MyHC expression and significantly increased myogenic fusion (p < 0.05) and myotube diameter (p < 0.05) indices back to control levels. EPA protective activity was associated with blocking cell death pathways as EPA completely attenuated TNF-mediated increases in caspase-8 activity (p < 0.05) and cellular necrosis (p < 0.05) back to their respective control levels. EPA alone significantly reduced spontaneous apoptosis and necrosis of differentiating myotubes (p < 0.001 and p < 0.05, respectively). A 2 hour pre-treatment with EPA, prior to treatment with TNF alone, gave similar results.

Conclusion

In conclusion, EPA has a protective action against the damaging effects of TNF-α on C2C12 myogenesis. These findings support further investigations of EPA as a potential therapeutic agent during skeletal muscle regeneration following injury.
BMP2 and BMP7 play antagonistic roles in feather induction
Authors: Michon Frederic , Forest Loïc , Collomb Elodie , Demongeot Jacques , Dhouailly Danielle
Published: July 2008

Feathers, like hairs, first appear as primordia consisting of an epidermal placode associated with a dermal condensation that is necessary for the continuation of their differentiation. Previously, the BMPs have been proposed to inhibit skin appendage formation. We show that the function of specific BMPs during feather development is more complex. BMP2 and BMP7, which are expressed in both the epidermis and the dermis, are involved in an antagonistic fashion in regulating the formation of dermal condensations, and thus are both necessary for subsequent feather morphogenesis. BMP7 is expressed earlier and functions as a chemoattractant that recruits cells into the condensation, whereas BMP2 is expressed later, and leads to an arrest of cell migration,likely via its modulation of the EIIIA fibronectin domain and α4 integrin expression. Based on the observed cell proliferation, chemotaxis and the timing of BMP2 and BMP7 expression, we propose a mathematical model, a reaction-diffusion system, which not only simulates feather patterning, but which also can account for the negative effects of excess BMP2 or BMP7 on feather formation.
Tissue-specific requirements of β-catenin in external genitalia development
Authors: Lin Congxing , Yin Yan , Long Fanxin , Ma Liang
Published: July 2008

External genitalia are body appendages specialized for internal fertilization. Their development can be divided into two phases, an early androgen-independent phase and a late androgen-dependent sexual differentiation phase. In the early phase, the embryonic anlage of external genitalia, the genital tubercle (GT), is morphologically identical in both sexes. Although congenital external genitalia malformations represent the second most common birth defect in humans, the genetic pathways governing early external genitalia development and urethra formation are poorly understood. Proper development of the GT requires coordinated outgrowth of the mesodermally derived mesenchyme and extension of the endodermal urethra within an ectodermal epithelial capsule. Here, we demonstrate that β-catenin plays indispensable and distinct roles in each of the aforementioned three tissue layers in early androgen-independent GT development. WNT-β-catenin signaling is required in the endodermal urethra to activate and maintain Fgf8 expression and direct GT outgrowth, as well as to maintain homeostasis of the urethra. Moreover, β-catenin is required in the mesenchyme to promote cell proliferation. By contrast, β-catenin is required in the ectoderm to maintain tissue integrity, possibly through cell-cell adhesion during GT outgrowth. The fact that both endodermal and ectodermal β-catenin knockout animals develop severe hypospadias in both sexes raises the possibility that the deregulation of any of these functions can contribute to the etiology of congenital external genital defects in humans.
Population Screening for Reproductive Risk for Single Gene Disorders in Australia: Now and the Future
Authors: Delatycki Martin B.
Published: July 2008

As the results of the Human Genome Project are realized, it has become technically possible to identify carriers of numerous autosomal and X-linked recessive disorders. Couples at risk of having a child with one of these conditions have a number of reproductive options to avoid having a child with the condition should they wish. In Australia the haemoglobinopathies are the only group of conditions for which population screening is widely offered and which is government funded. In some Australian states there are also population screening programs for cystic fibrosis and autosomal recessive conditions more common in Ashkenazi Jewish individuals which are generally offered on a user pays basis. It is predicted that as consumer demand increases and testing becomes cheaper, that many people planning or in the early stages of pregnancy will have carrier screening for multiple genetic conditions. This will have significant implications for genetic counseling, laboratory and prenatal testing resources. In addition such screening raises a number of ethical issues including the value of lives of those born with genetic conditions for which screening is available.
Regularisierungsverfahren für die Identifikation mittels lokal-affiner Modelle (Regularization Techniques for Identification Using Local-Affine Models)
Authors: Zimmerschied Ralf , Isermann Rolf
Published: July 2008

Untersucht werden Regularisierungsverfahren für die Identifikation nichtlinearer dynamischer Systeme mittels lokal-affiner Modelle. Die implizite Regularisierung durch lokale Parameterschätzung in Gleichungsfehler-Anordnung wird einer expliziten Regularisierung nach Tikhonov mit globaler Parameterschätzung in Ausgangsfehler-Anordnung gegenübergestellt. Nach Beschreibung von exakter und approximativer Tikhonov-Regularisierung zweiter Ordnung wird ein neuartiger global-lokaler Regularisierungsoperator speziell für lokal-affine Modelle hergeleitet, der die lokale Interpretierbarkeit der Teilmodelle garantiert.
A Description of the Trials, Reviews, and Practice Guidelines Indexed in the PEDro Database
Authors: Maher Christopher G , Moseley Anne M , Sherrington Cathie , Elkins Mark R , Herbert Robert D
Published: July 2008

This perspective provides an overview of the randomized controlled trials, systematic reviews, and evidence-based clinical practice guidelines in physical therapy. Data from the Physiotherapy Evidence Database (PEDro) are used to describe key events in the history of physical therapy research and the growth of evidence of effects of interventions used in the various subdisciplines of physical therapy. The 11,494 records that were identified reveal a rich history of physical therapy research dating back to the first trial in 1929. Most of the randomized controlled trials, systematic reviews, and evidence-based clinical practice guidelines in physical therapy have been published since the year 2000. This rapid growth presents a challenge for physical therapists who want to keep up to date in clinical practice.
MLA Regional Journals: Accountability, Innovation
Authors: Roth Laurence
Published: July 2008

All scholarly journals face similar challenges – small audiences, tight budgets, and editorial policies and practices that sometimes harden into dogma. Modern Language Association (MLA) regional journals offer a focused example of how member-driven scholarly journals can meet these challenges and, in doing so, change our notions of what such journals can do and how they should look. As publications of smaller-scale professional organizations, MLA regional journals are in a good position to hear and act on their members’ needs; when the duty of serving those members is carried out in an entrepreneurial spirit, editors open up, and can take advantage of, new opportunities for publishing. 1
Image-injected frameless stereotactic approach to the anterior craniovertebral junction
Authors: Ryken Timothy , Julien Terrence , Frankel Bruce , Canute Greg , Haller John , Rosenbaum Arthur
Published: July 2008

Transoral odontoidectomy is often performed in the treatment of cervicomedullary junction disease. The operating microscope is frequently used to improve visualization in this narrow field of view. In the setting of complex anatomy or surgical revision the authors hypothesized that combining frameless stereotactic technique with intraoperative microscopy would improve the ability to visualize and identify intraoperative anatomy. In addition they believed that the ability to visualize the targeted region directly in the operating microscope "image injection" would be of particular interest in this setting, provided that sufficient accuracy for use could be obtained in the registration process. The authors assessed the efficacy of this approach in a cadaveric model and obtained sufficient accuracy to warrant use in the operating room. This technique was applied in the surgical management of a 56-year-old woman with rheumatoid arthritis who had undergone a previous decompressive transoral procedure. Subsequently she suffered progressive deterioration and was found to have residual bony compression of the anterior cervicomedullary junction. The authors performed decompressive surgery and obtained satisfactory results by using the image-injected technique, and the patient experienced subsequent clinical improvement. The authors conclude that the image-injected frameless stereotactic technique is of potential benefit, particularly in the narrow window of approach of the transoral odontoidectomy.
Efficacy of dural tenting sutures
Authors: Winston Ken R.
Published: July 2008

Object

The goal of this study was to assess the necessity for the prophylactic use of dural tenting sutures.

Methods

Data that had been prospectively collected from 369 consecutive cranial operations in adults were analyzed. In this series of patients, dural tenting sutures were used on a judicious "as needed" basis. They were never used to satisfy a procedural routine or for use as a prophylaxis against epidural hemorrhage that was not apparent. The sutures were used for the control of epidural bleeding in 33 patients (8.9%); no tenting was required in 336 patients (91.1%). Reoperation for postoperative epidural hematoma was not required in this series.

Conclusions

Dural tenting sutures continue to have an important role in neurosurgery; however, there is no compelling evidence to support their traditional prophylactic use in every intracranial operation.
Dorsoproximal proximal phalanx osteochondral fragmentation in 117 Warmblood horses
Authors: Martens A. , Maes D. , Boussauw B. , Forsyth R. , Boening K. J. , Declercq J.
Published: July 2008

The objective of the present study was to determine clinical and arthroscopic characteristics associated with dorso-proximal proximal phalanx (P1) fragments in Warmblood horses, as well as to examine their histopathological appearance. One hundred sixty-eight fragments were removed from 150 fetlocks of 117 Warmblood horses. Details of signalment and results of clinical examination were collected prior to surgery. After arthroscopic fragment removal and joint evaluation for synovial and/or cartilage abnormalities, the fragments were measured and evaluated histopathologically. The vast majority of the fragments (95.2%) were found medially, without predilection for front or hind limbs. In 10% of the joints, more than one fragment was present. The mean size of the fragments was 6.8 ± 2.6 mm. Only eight horses presented fetlock-related lameness. Horses of seven years of age and older (OR=13.32; p=0.033) and the presence of more than one fragment (OR=11.12; p=0.016) were significantly associated with lameness. Arthroscopic evaluation revealed one or more abnormalities in 50.7% of the joints. On histopathology, osteochondral fragments presented as a bony center covered with smooth hyaline cartilage on one side and some fibrous tissue on the other side. No clear histopathological signs were indicating precisely their origin. In Warmblood horses with dorsoproximal P1 fragments, the age (seven years and older) and the presence of more than one fragment in a fetlock significantly increased the risk of lameness. The osteochondral dorsoproximal P1 fragments could be defined as a developmental orthopaedic disease.
Nature‐Inspired Boiling Enhancement by Novel Nanostructured Macroporous Surfaces
Authors: Li Shanghua , Furberg Richard , Toprak Muhammet S. , Palm Björn , Muhammed Mamoun
Published: July 2008

World energy crisis has triggered more attention to energy saving and energy conversion systems. Enhanced surfaces for boiling are among the applications of great interest since they can improve the energy efficiency of heat pumping equipment (i.e., air conditioners, heat pumps, refrigeration machines). Methods that are used to make the state‐of‐the‐art enhanced surfaces are often based on complicated mechanical machine tools, are quite material‐consuming and give limited enhancement of the boiling heat transfer. Here, we present a new approach to fabricate enhanced surfaces by using a simple electrodeposition method with in‐situ grown dynamic gas bubble templates. As a result, a well‐ordered 3D macro‐porous metallic surface layer with nanostructured porosity is obtained. Since the structure is built based on the dynamic bubbles, it is perfect for the bubble generation applications such as nucleate boiling. At heat flux of 1 W  cm‐2, the heat transfer coefficient is enhanced over 17 times compared to a plain reference surface. It's estimated that such an effective boiling surface would improve the energy efficiency of many heat pumping machines with 10–30%. The extraordinary boiling performance is explained based on the structure characteristics.
Fibrillar Constructs from Multilevel Hierarchical Self‐Assembly of Discotic and Calamitic Supramolecular Motifs
Authors: Houbenov Nikolay , Nykänen Antti , Iatrou Hermis , Hadjichristidis Nikos , Ruokolainen Janne , Faul Charl F. J. , Ikkala Olli
Published: July 2008

We here report on polymeric solid‐state self‐assembly leading to organization over six length scales, ranging from the molecular scale up to the macroscopic length scale. We combine several concepts, i.e., rod‐like helical and disc‐like liquid crystallinity, block copolymer self‐assembly, DNA‐like interactions to form an ionic polypeptide–nucleotide complex and packing frustration to construct mesoscale fibrils. Ionic complexation of anionic deoxyguanosine monophosphate (dGMP) and triblock coil–rod–coil copolypeptides is used with cationic end blocks and a helical rod‐like midblock. The guanines undergo Hoogsteen pairing to form supramolecular discs, they π‐stack into columns that self‐assemble into hexagonal arrays that are controlled by the end blocks. Packing frustration between the helical rods from the block copolymer midblock and the discotic motif limits the lateral growth of the assembly thus affording mesoscale fibrils, which in turn, form an open fibrillar network. The concepts suggest new rational methodologies to construct structures on multiple length scales in order to tune polymer properties.
Carbon Nanotube Gas and Vapor Sensors
Authors: Kauffman Douglas R. , Star Alexander
Published: July 2008

Carbon nanotubes have aroused great interest since their discovery in 1991. Because of the vast potential of these materials, researchers from diverse disciplines have come together to further develop our understanding of the fundamental properties governing their electronic structure and susceptibility towards chemical reaction. Carbon nanotubes show extreme sensitivity towards changes in their local chemical environment that stems from the susceptibility of their electronic structure to interacting molecules. This chemical sensitivity has made them ideal candidates for incorporation into the design of chemical sensors. Towards this end, carbon nanotubes have made impressive strides in sensitivity and chemical selectivity to a diverse array of chemical species. Despite the lengthy list of accomplishments, several key challenges must be addressed before carbon nanotubes are capable of competing with state‐of‐the‐art solid‐state sensor materials. The development of carbon nanotube based sensors is still in its infancy, but continued progress may lead to their integration into commercially viable sensors of unrivalled sensitivity and vanishingly small dimensions.
Immunoaffinity capillary electrophoresis as a powerful strategy for the quantification of low‐abundance biomarkers, drugs, and metabolites in biological matrices
Authors: Guzman Norberto A. , Blanc Timothy , Phillips Terry M.
Published: July 2008

In the last few years, there has been a greater appreciation by the scientific community of how separation science has contributed to the advancement of biomedical research. Despite past contributions in facilitating several biomedical breakthroughs, separation sciences still urgently need the development of improved methods for the separation and detection of biological and chemical substances. In particular, the challenging task of quantifying small molecules and biomolecules, found in low abundance in complex matrices (e.g., serum), is a particular area in need of new high‐efficiency techniques. The tandem or on‐line coupling of highly selective antibody capture agents with the high‐resolving power of CE is being recognized as a powerful analytical tool for the enrichment and quantification of ultra‐low abundance analytes in complex matrices. This development will have a significant impact on the identification and characterization of many putative biomarkers and on biomedical research in general. Immunoaffinity CE (IACE) technology is rapidly emerging as the most promising method for the analysis of low‐abundance biomarkers; its power comes from a three‐step procedure: (i) bioselective adsorption and (ii) subsequent recovery of compounds from an immobilized affinity ligand followed by (iii) separation of the enriched compounds. This technology is highly suited to automation and can be engineered to as a multiplex instrument capable of routinely performing hundreds of assays per day. Furthermore, a significant enhancement in sensitivity can be achieved for the purified and enriched affinity targeted analytes. Thus, a compound that exists in a complex biological matrix at a concentration far below its LOD is easily brought to well within its range of quantification. The present review summarizes several applications of IACE, as well as a chronological description of the improvements made in the fabrication of the analyte concentrator–microreactor device leading to the development of a multidimensional biomarker analyzer.
Survival of patients with neck recurrence following radical neck dissection: Utility of a second neck dissection?
Authors: Jones Andrew S. , Tandon Sankalap , Helliwell Timothy R. , Husband David J. , Jones Terence M.
Published: July 2008

Treatment of neck recurrence following radical neck dissection is extremely difficult. Retrospective review of 699 radical neck dissections was performed. Recurrence rates, host, tumor, treatment factors, and survival were analyzed. One hundred nineteen patients who had undergone radical neck dissections had recurrence, 69 were considered candidates for salvage surgery. Factors that increased the risk of neck recurrence were neck node (N) status and no adjuvant radiotherapy. Factors associated with radical salvage treatment were young age, good general condition, and low recurrent N classification. Five‐year survival for salvage neck dissection was 31%. Young patients and low T and N classification did well. Low recurrent N classification and salvage surgery were associated with good prognosis for recurrence. In our study, radical neck dissection has a regional failure rate of 20%, a third of recurrence cases were offered curative treatment. Of these, 31% were cured with salvage surgery. © 2008 Wiley Periodicals, Inc. Head Neck 2008
State of head and neck surgical oncology research—A review and critical appraisal of landmark studies
Authors: Higgins Kevin M. , Wang Jenny R.
Published: July 2008

Surgical literature has been criticized for the lack of high‐quality research. The present review examines methodological quality of literature published in head and neck surgical oncology. We focus on landmark studies published on topics of best practice controversy, namely (1) the role of chemotherapy and organ‐preservation protocols in the management of head and neck mucosal malignancies; (2) the role of selective neck dissection versus radical neck dissection; and (3) the role of laser microsurgery in the management of larynx cancer. Similar flaws were evident in selected landmark studies with the major issue being multiplicity in the form of multiple outcome analysis, comparison of multiple treatment groups, repeated measures over time, planned interim analyses, and subgroup analyses. The open nonrandomized controlled trial may be a feasible option in head and neck surgical research allowing for standardization, uniformity, consistency, and blinded outcome assessment. © 2008 Wiley Periodicals, Inc. Head Neck 2008
Treatment results of bisphosphonate‐related osteonecrosis of the jaws
Authors: Wutzl Arno , Biedermann Edwin , Wanschitz Felix , Seemann Rudolf , Klug Clemens , Baumann Arnulf , Watzinger Franz , Schicho Kurt , Ewers Rolf , Millesi Gabriele
Published: July 2008

Background.

Osteonecrosis of the jaws occurs after the administration of bisphosphonates. An unequivocal treatment strategy is yet to be devised. We assess the treatment of patients with bisphosphonate‐related osteonecrosis of the jaws (BRONJ).

Methods.

The investigators studied a prospective cohort of 58 patients 6 months after surgical treatment of BRONJ. Outcome variables were the status of the mucosa, the visual analog score of pain, and prosthetic rehabilitation. Preoperative staging results were compared with the postoperative outcome and statistically evaluated.

Results.

Of 58 patients, 41 surgically treated patients could be followed up after a mean period of 189 (±23) days. Twenty‐four (58.5%) were free of pain and had an intact mucosa. A statistically significant improvement was registered between preoperative and postoperative staging (p <.01); 11 of 12 patients who had been treated with a flap procedure for soft tissue closure had an intact mucosa.

Conclusions.

This is the first prospective study to report the outcome of treatment in a cohort of patients with BRONJ. Minimal resection of necrotic bone and local soft tissue closure might be a feasible treatment strategy in patients with established BRONJ. © 2008 Wiley Periodicals, Inc. Head Neck 2008
Variations of supraorbital foramina in living subjects evaluated with multidetector computed tomography
Authors: Turhan‐Haktanır Nurten , Ayçiçek Abdullah , Haktanır Alpay , Demir Yavuz
Published: July 2008

Background.

We aimed to evaluate the anatomic variations of supraorbital foramina/notches in living subjects using multidetector CT (MDCT) related to age, sex, and side.

Methods.

Computer records of 399 patients (207 men and 192 women) referred for high‐resolution CT examinations were evaluated for presence, shape, width, and distance from the nasion.

Results.

The most common presentation was single notch. Presence of double foramen/notch was higher in the right. Bilateral notches were wider in men. Bilateral foramina and left notches were located more lateral in men. Notches were closer to nasion than foramina. Positive correlations were found between right and left sides for the diameters and distances to nasion. Widths of foramina showed negative correlation with the distances to nasion.

Conclusions.

This is the first study showing supraorbital foramen/notch variations in living crania. MDCT should be established in anatomical studies and may be used in preoperative evaluation. © 2008 Wiley Periodicals, Inc. Head Neck 2008
Primary squamous cell carcinoma of Stensen's duct in a patient with HIV: The role of magnetic resonance imaging and fine‐needle aspiration
Authors: Kim Theresa B. , Klein Harvey Z. , Glastonbury Christine M. , Eisele David W.
Published: July 2008

Background.

Primary malignant tumors involving Stensen's duct are rare neoplasms, with less than 30 cases reported. We report a case of primary squamous cell carcinoma (SCC) involving Stensen's duct in a patient infected with human immunodeficiency virus (HIV) and describe the role of fine‐needle aspiration (FNA) and MRI in the diagnosis of this rare entity.

Methods.

A 47‐year‐old man with HIV presented with intermittent parotid swelling and pain unresponsive to conservative treatment. He subsequently developed a mass emanating from Stensen's duct, and an MRI and ultrasound‐guided FNA revealed carcinoma of Stensen's duct. Total parotidectomy with postoperative external beam radiation therapy was performed.

Results.

The patient remains disease free 31 months after treatment.

Conclusions.

Primary SCC of Stensen's duct is a rare entity that may mimic benign obstructive parotid disease. FNA and MRI are useful in the diagnosis and assessment of disease extent. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
Intercomparison of remote sensing‐based models for estimation of evapotranspiration and accuracy assessment based on SWAT
Authors: Gao Yanchun , Long Di
Published: July 2008

An intercomparison of daily actual evapotranspiration (ET) estimates from the single‐source models (SEBAL and SEBS) and the two‐source models (P‐TSEB and S‐TSEB) using remotely sensed data was performed to examine their utilities and limitations under a wide range of land covers and different meteorological conditions. The accuracy of ET estimates from remote sensing‐based models of a selected watershed on 23 June 2005 (DOY 174) presenting large air drying power and marked contrast in underlying surface characteristics, and 25 July 2005, (DOY 206) in contrast to the meteorological and underlying surface conditions of DOY 174, were evaluated in terms of SWAT‐based ET. The ET estimates from the two methodologies are shown to be comparable, indicating that S‐TSEB has the highest accuracy with relative errors of 2·2% and 5·6% with reference to SWAT‐based ET for DOY 174 and 206, respectively. Hence it was selected to be the basis for performing an intercomparison with other remote sensing‐based models. Single‐source models are very sensitive to KB−1 parameter, rendering marked differences in ET estimates because of different treatments of roughness length for heat transfer. SEBAL and SEBS yielded mean absolute percentage difference (MAPD) versus S‐TSEB within 26·22% and 26·56% for DOY 174 and within 9·11% and 11·69% for DOY 206, respectively, indicating their applicability to higher vegetation cover and soil moisture availability areas under small air drying power condition. P‐TSEB generated MAPD versus S‐TSEB within 41·15% for DOY 174 and 8·79% for DOY 206, implying that P‐TSEB is highly consistent with S‐TSEB under small air drying power and less contrast in soil moisture conditions, whereas noticeable discrepancies occur under large air drying power and marked contrast in soil moisture circumstances, in particular for sparse cover. The performance of P‐TSEB largely depends on the meteorological and underlying surface conditions, both exerting significant influences on the extent of coupling between vegetation and soil. Copyright © 2008 John Wiley & Sons, Ltd.
Staying at the table: building sustainable community–research partnerships
Authors: Rappaport Nancy , Alegria Margarita , Mulvaney‐Day Norah , Boyle Barbara
Published: July 2008

In this study, the authors identify three guiding principles or relational strategies for developing successful community partnerships and building an alliance for systemic change. These principles were derived from their work over 4 years with an urban public school system, which was focused on generating a series of interventions for improving the behavioral and academic functioning of immigrant students. In their process, they developed an analysis and monitoring system of students' progress, which allowed for earlier targeted effective support. © 2008 Wiley Periodicals, Inc.
Biliary fascioliasis: Sonographic appearance patterns
Authors: Yesildag Ahmet , Yıldız Harun , Demirci Mustafa , Gören İbrahim , İşler Mehmet
Published: July 2008

Purpose.

To describe the sonographic findings of biliary fascioliasis.

Method.

The study included 27 patients with fascioliasis and abdominal sonographic findings in biliary system. All diagnoses were confirmed via serologic enzyme‐linked immunosorbent assay, and 5 patients underwent cholecystectomy. Sonographic findings in the biliary system were defined as primary and secondary.

Results.

Primary findings included spontaneously moving echogenic structures, linear echoes, curvilinear echoes, oval‐shaped echogenic structure, matted echogenic particle, echogenic particle adherent to the gallbladder wall, motionless freely floating round echogenic foci, and leaf‐like echogenic structures. Secondary findings were dilatation or wall thickening of the biliary system. In the liver, multiple confluent subcapsular nodules were also noted on sonography and CT in 14 of 27 patients.

Conclusion.

Sonography can detect biliary system lesions in fascioliasis and can aid diagnosis of the disease. However, the radiologist should be familiar with the different sonographic appearances of biliary fascioliasis. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2009
Maximizing peak capacity and separation speed in liquid chromatography
Authors: Petersson Patrik , Frank Andre , Heaton James , Euerby Melvin R.
Published: July 2008

The practical effects of gradient time and flow rate on the peak capacities of a range of analytes of differing molecular weights (MWs) and physico‐chemical properties have been evaluated using ultra high pressure LC instrumentation with sub‐2 μm and superficially porous particle phases. Optimum peak capacity, in RP gradient LC, for small molecules, including typical pharmaceutical drugs and peptides with MWs up to 1300, was demonstrated at a maximum flow rate for a given gradient time (i.e. up to 40 min). Flow rates significantly higher than the optimum in the van Deemter plots and also higher than those typically employed by the majority of the chromatographers today are recommended for gradient LC (i.e. up to 1.0 mL/min on 50–150×2.1 mm 1.7 μm columns). This recommendation is applicable for temperatures above 40°C, i.e. temperatures typically utilized for separations employing sub‐2 μm particles to reduce column back pressure. Van Deemter and pseudo van Deemter plots were determined and combined with chromatographic gradient elution theory to explain our unexpected observations. The derived models exhibited good agreement between experimental and predicted peak capacities (absolute average error 4%, max. error 12%).
Stearidonic acid: A plant produced omega‐3 PUFA and a potential alternative for marine oil fatty acids
Authors: Coupland Keith
Published: July 2008

Omega‐3 (n‐3) fatty acids are widely recognized as being important in regulating many inflammatory disorders in man. However, metabolism of the parent n‐3 fatty acid α‐linolenic acid (ALA, 18:3n‐3) to the highly unsaturated bioactive fatty acids; eicosapentaenoic acid (EPA, 20:5n‐3) and docosahexaenoic acid (DHA, 22:6n‐3), in the body is limited. The first product in the pathway leading to EPA/DHA is the post‐Δ6 desaturase metabolite stearidonic acid (SDA, 18:4n‐3). The activity of the Δ6‐desaturase enzyme is low in man and can be adversely influenced by several environmental factors including dietary fat. SDA has been shown, in several studies, to be rapidly and efficiently converted to EPA which is a probable factor in its bio‐activity. The main source of EPA and DHA in diet is fish oil which, owing to over‐fishing and its extensive use in aquaculture feed, is becoming a scarce resource. There clearly exists a need for a renewable source of a lipid containing the highly unsaturated n‐3 fatty acids EPA, DHA or SDA. Although the highly unsaturated fatty acids (HUFA) have been commercially produced in micro‐organisms neither EPA nor DHA has been shown to exist in any quantity in land‐based plants. SDA is however found in several fungal and algal species and also in a small number of plant seed oils. Plants from the Boraginaceae family notably Echium species are particularly rich in SDA and Echium plantagineum has been grown commercially. Other plants from the Boraginaceae are being investigated and several have been identified that may offer benefits over Echium spp. Transgenic plants containing high levels of SDA have also been reported but engineering EPA or DHA into genetically modified higher plants is proving elusive. SDA‐containing lipids are of great interest in a number of areas such as fortified foods, dietary supplements, medicinal foods, pharmaceuticals and personal‐care products.