bluuebunny/crossref_metadata_2025 huggingface dataset:
Interval timing in genetically modified mice: a simple paradigm
Authors: Balci F. , Papachristos E. B. , Gallistel C. R. , Brunner D. , Gibson J. , Shumyatsky G. P.
Published: August 2007

We describe a behavioral screen for the quantitative study of interval timing and interval memory in mice. Mice learn to switch from a short‐latency feeding station to a long‐latency station when the short latency has passed without a feeding. The psychometric function is the cumulative distribution of switch latencies. Its median measures timing accuracy and its interquartile interval measures timing precision. Next, using this behavioral paradigm, we have examined mice with a gene knockout of the receptor for gastrin‐releasing peptide that show enhanced (i.e. prolonged) freezing in fear conditioning. We have tested the hypothesis that the mutants freeze longer because they are more uncertain than wild types about when to expect the electric shock. The knockouts however show normal accuracy and precision in timing, so we have rejected this alternative hypothesis. Last, we conduct the pharmacological validation of our behavioral screen using d‐amphetamine and methamphetamine. We suggest including the analysis of interval timing and temporal memory in tests of genetically modified mice for learning and memory and argue that our paradigm allows this to be done simply and efficiently.
Serum components and activated Ha‐ras antagonize expression of perivenous marker genes stimulated by β‐catenin signaling in mouse hepatocytes
Authors: Braeuning Albert , Menzel Moritz , Kleinschnitz Eva‐Maria , Harada Naomoto , Tamai Yoshitaka , Köhle Christoph , Buchmann Albrecht , Schwarz Michael
Published: August 2007

Hepatocytes of the periportal and perivenous zones of the liver lobule show marked differences in the contents and activities of many enzymes and other proteins. Previous studies from our and other groups have pointed towards an important role of β‐catenin‐dependent signaling in the regulation of expression of genes encoding proteins with preferential perivenous localization, whereas, in contrast, signaling through Ras‐dependent pathway(s) may induce a ‘periportal’ phenotype. We have now conducted a series of experiments to further investigate this hypothesis. In transgenic mice with scattered expression of an activated Ha‐ras (Ha‐rasG12V) mutant in liver, expression of the perivenous markers glutamine synthetase and two cytochrome P450 isoforms was completely abolished in those hepatocytes demonstrating constitutively activated extracellular signal‐regulated kinase activity, even though they were located directly adjacent to central veins. Similarly, incubation of primary hepatocytes or hepatoma cells with increasing amounts of serum caused a concentration‐dependent attenuation of expression of perivenous marker mRNAs, whereas the expression of periportal markers was increased. The inhibitory effect of high amounts of serum on the expression of perivenous markers was also observed if their expression was stimulated by activation of β‐catenin signaling, and comparable inhibitory effects were seen in cells stably transfected with a T‐cell factor/lymphoid‐enhancing factor‐driven luciferase reporter. Epidermal growth factor could partly mimic serum effects in hepatoma cells, and its effect could be blocked by an inhibitor of extracellular signal‐regulated kinase activity. These data suggest that activation of the Ras/mitogen‐activated protein kinase (extracellular signal‐regulated kinase) pathway favors periportal gene expression while simultaneously antagonizing a perivenous phenotype of hepatocytes.
Anti‐Emetic Therapy in Cancer Chemotherapy: Current Status
Authors: Herrstedt Jørn , Dombernowsky Per
Published: August 2007

Abstract:   Nausea and vomiting are ranked as the most severe side effects to chemotherapy by cancer patients. Twenty years ago, treatment of nausea and vomiting from chemotherapy only had moderate effect and often unpleasant side effects. The drugs used included dopamine2‐receptor antagonists and corticosteroids alone or combined. This review summarizes the development of anti‐emetic therapy, but will focus on the importance of two new classes of anti‐emetics: the serotonin3‐ and the neurokinin1‐receptor antagonists. Furthermore, evidence‐based guidelines for the treatment of chemotherapy‐induced nausea and vomiting will be given. The serotonin3‐receptor antagonists, the first group of drugs developed specifically as anti‐emetics, have significantly improved the prophylaxis of chemotherapy‐induced emesis especially in combination with a corticosteroid. The improvement in the prophylaxis of nausea with this combination is however modest. A new group of anti‐emetics, the neurokinin1‐receptor antagonists, has now been developed, and the first drug, aprepitant, was marketed in 2003. Aprepitant increases the effect of a serotonin3‐receptor antagonist plus a corticosteroid against acute emesis induced by highly or moderately emetogenic chemotherapy and aprepitant is also active in the protection against delayed emesis. The importance of drug–drug interactions with anti‐emetics and other drugs, especially cytotoxins, through their competition for cytochrome P450 enzymes, have been studied. At present, there is no evidence that such interactions are of major clinical importance. Evidence‐based clinical guidelines are now available and regularly updated, but unfortunately clinical implementation is slow. Recommendations for some types of chemotherapy‐induced emesis such as delayed emesis, is based on a low level of evidence. Furthermore, the majority of clinical trials include highly selected groups of patients not permitting definite conclusions for other and more heterogeneous patient groups. Development of new anti‐emetics with other mechanisms of action is awaited with interest.
Application of Orem's Self‐Care Deficit Theory and Standardized Nursing Languages in a Case Study of a Woman with Diabetes
Authors: Kumar Coleen P.
Published: August 2007

PURPOSE.  This paper aims to illustrate the process of theory‐based nursing practice by presenting a case study of a clinical nurse specialist's assessment and care of a woman with type 2 diabetes.

DESIGN.  Orem's self‐care deficit theory and standardized nursing language, NANDA, NIC (Nursing Interventions Classification), and NOC (Nursing Outcomes Classification), guided assessment and the identification of outcomes and interventions related to the client's management of diabetes.

FINDINGS.  Theory‐based nursing care and standardized nursing language enhanced the client's ability to self‐manage the chronic illness: diabetes.

CONCLUSION.  Nursing theory and standardized nursing language enhance communication among nurses and support a client's ability to self‐manage a chronic illness.
Comparison of developmental trajectories in the starlet sea anemoneNematostella vectensis:embryogenesis, regeneration, and two forms of asexual fission
Authors: Reitzel Adam M. , Burton Patrick M. , Krone Cassandra , Finnerty John R.
Published: August 2007

Abstract.The starlet sea anemone,Nematostella vectensis, is a small burrowing estuarine animal, native to the Atlantic coast of North America. In recent years, this anemone has emerged as a model system in cnidarian developmental biology. Molecular studies of embryology and larval development inN. vectensishave provided important insights into the evolution of key metazoan traits. However, the adult body plan ofN. vectensismay arise via four distinct developmental trajectories: (1) embryogenesis following sexual reproduction, (2) asexual reproduction via physal pinching, (3) asexual reproduction via polarity reversal, and (4) regeneration following bisection through the body column. Here, we compare the ontogenetic sequences underlying alternate developmental trajectories. Additionally, we describe the predictable generation of anomalous phenotypes that can occur following localized injuries to the body column. These studies suggest testable hypotheses on the molecular mechanisms underlying alternate developmental trajectories, and they provoke new questions about the evolution of novel developmental trajectories and their initiation via environmental cues.
The body size of the New Zealand orb‐weaving spider Waitkera waitakerensis (Uloboridae) is directly related to temperature and affects fecundity
Authors: Opell Brent D. , Berger Andrea M. , Shaffer Rachel S.
Published: August 2007

Abstract. Waitkera waitakerensis occupies lowland forests of New Zealand's North Island, where temperatures decrease in a southwestward direction. The mean annual temperatures of 18 collecting sites, as extracted from GIS data, are directly related to the first femur length of adult females. Neither site elevation nor phylogeny affected spider size or other variables examined. The direct relationship between spider body size and environmental temperature followed a pattern observed in other terrestrial arthropods with a univoltine life cycle and can probably be explained by the longer growing season of warmer regions. Egg diameter was uniform across the species. Site temperature and female first femur length were each directly related to the number of eggs deposited in egg sacs. The date of egg sac collection was inversely related to egg number, suggesting that clutch size declines during the reproductive season. Females deposit eggs beneath a triangular platform and then cover them with a lower silk sheet. The area of this upper platform and the volume of the egg sac were each directly related to egg number, but not to female first femur length. The depth of the lower covering was not related to egg number or to spider first femur length. This suggests that spiders use information about the volume of eggs in their abdomens to construct an egg sac whose volume will accommodate the volume of eggs to be laid and that females do so principally by adjusting the size of the sac's upper triangular platform.
Stereological analysis of nutritive phagocytes and gametogenic cells during the annual reproductive cycle of the green sea urchin, Strongylocentrotus droebachiensis
Authors: Harrington Laura H. , Walker Charles W. , Lesser Michael P.
Published: August 2007

Abstract. The germinal epithelium of sea urchin gonads contains two interdependent populations of cells: somatic cells called nutritive phagocytes (NPs) and germ cells—ovarian and testicular gonial cells and their derivatives, gametocytes and gametes. Annually, NPs vary their structure and function to produce a changing microenvironment for germ cells during gametogenesis and after spawning. Here, we describe seasonal changes in the NPs as they interact with germ cells during successive gametogenic stages in both sexes of the green sea urchin, Strongylocentrotus droebachiensis. Monthly samples were collected from the Gulf of Maine at a depth of 10 m and analyzed with light microscopy and stereology. Shorter day length and falling seawater temperatures were correlated with nutrient mobilization from NPs, initiation of gonial cell mitosis, and subsequent gametogenesis. During gametogenesis, NPs in both sexes were depleted of nutrients and eventually phagocytize residual ova or spermatozoa. Observations from this study are important for understanding both the cellular aspects of the reproductive biology of sea urchins and those environmental factors that affect the onset and progress of gametogenesis.
A synchrotron superbubble in the IC 10 galaxy: a hypernova remnant?
Authors: Lozinskaya T. A. , Moiseev A. V.
Published: August 2007

The nature of the synchrotron superbubble in the IC 10 galaxy is discussed using the results of our investigation of its ionized gas structure, kinematics and emission spectrum from observations made with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences, and based on our analysis of the radio emission of the region. The hypernova explosion is shown to be a more plausible mechanism of formation of the synchrotron superbubble compared with the earlier proposed model of multiple supernova explosions. A compact remnant of this hypernova may be identified with the well-known X-ray binary X-1 – an accreting black hole.
The Amenity Complex: Towards a Framework for Analysing and Predicting the Emergence of a Multifunctional Countryside in Australia
Authors: ARGENT NEIL , SMAILES PETER , GRIFFIN TREVOR
Published: August 2007

There is growing consensus among academics, regional development organisations and rural communities that the future growth and development of rural regions is increasingly dependent upon their ability to convey, to both established and prospective residents, the ‘amenity’ of their local physical, social and economic environments. However, little research to date has sought to identify exactly what comprises ‘amenity’ in the rural context, or has examined how this conceptually slippery quality is distributed across rural Australia, or how it influences local demographic, socio‐economic and land use change. This paper attempts a broad scale investigation of rural amenity in the south‐east Australian ecumene, identifying its core components in this context, mapping its distribution and assessing the nature of its influence over in‐migration rates over the past three decades. The paper finds that, at a macro‐scale, amenity tends to follow a general gradient from high to low according to distance from the coast, and that its relationship with in‐migration rates has increased substantially between 1976–1981 and 1996–2001.
NRM Regions in Australia: the ‘Haves’ and the ‘Have Nots’
Authors: ROBINS LISA , DOVERS STEPHEN
Published: August 2007

This paper identifies external factors affecting the capacity of Australia's now‐formalised 56 regional natural resource management (NRM) bodies and their community‐based Boards to meet planning and management responsibilities. It demonstrates that little is known about the basic capacity‐related characteristics of NRM regions, despite the lengthy and elaborate process of regionalism that Australia has embarked upon, with its associated and substantial devolution of responsibilities and resources. A suite of indicators is used to develop an ‘exploratory’ capacity typology of NRM regions. The ten regional ‘types’ identified are found to attract varying budget allocations under the Natural Heritage Trust Extension and National Action Plan for Salinity and Water Quality. There are indications that State and regional interests within and outside NRM can significantly influence the distribution of resources. An examination of resources allocated to capacity‐building activities shows significant differences between regions in the scale of resources allocated (0–96% of total budget). The paper argues the case for intervention to reduce the gap between ‘have’ and ‘have not’ regions, and for further exploration of disparities in the allocation of resources to capacity‐building activities. Clarification is needed of the extent to which capacity‐building activities adequately target regional NRM bodies and their Boards.
Hidden Spaces of Resistance of the Subordinated: Case Studies from Vietnamese Female Migrant Partners in Taiwan
Authors: Wang Hong-zen
Published: August 2007

This paper explores how contradictory social structures influence power relations between “Vietnamese brides” and their Taiwanese family members. By analyzing two aspects of interaction between “Vietnamese brides” and their husbands' families, i.e., how the families require them to integrate into Taiwanese society and what strategies they employ to escape from these constraints, we argue that contradictory social relations together with commodified marriage and liminality help them to develop strategies of escape into the “hidden space.” The development of these strategies indicates one thing: hegemony is never fully achieved – it is always negotiated and contested.
Ethnic Self-Identification of First-Generation Immigrants
Authors: Zimmermann Laura , Zimmermann Klaus F. , Constant Amelie
Published: August 2007

This paper uses the concept of ethnic self-identification of immigrants in a two-dimensional framework. It acknowledges that attachments to both the country of origin and the host country are not necessarily mutually exclusive. There are three possible paths of adjustment from separation at entry, namely the transitions to assimilation, integration, and marginalization. We analyze the determinants of ethnic self-identification in this process using samples of first-generation male and female immigrants, and controlling for pre- and post-immigration characteristics. While we find strong gender differences, a wide range of pre-immigration characteristics like education in the country of origin are not important.
Prevalence and breed distribution of chronic pancreatitis at post‐mortem examination in first‐opinion dogs
Authors: Watson P. J. , Roulois A. J. A. , Scase T. , Johnston P. E. J. , Thompson H. , Herrtage M. E.
Published: August 2007

Objectives:To assess the prevalence of canine chronic pancreatitis in first‐opinion practice and identify breed associations or other risk factors.

Methods:Three sections of pancreas were taken from 200 unselected canine post‐mortem examinations from first‐opinion practices. Sections were graded for inflammation, fibrosis and other lesions. Prevalence and relative risks of chronic pancreatitis and other pancreatic diseases were calculated.

Results:The prevalence of chronic pancreatitis was 34 per cent omitting the autolysed cases. Cavalier King Charles spaniels, collies and boxers had increased relative risks of chronic pancreatitis; cocker spaniels had an increased relative risks of acute and chronic pancreatitis combined. Fifty‐seven per cent of cases of chronic pancreatitis were classified histologically as moderate or marked. Forty‐one per cent of cases involved all three sections. Dogs with chronic pancreatitis were more commonly female and overweight, but neither factor increased the relative risk of chronic pancreatitis. There were breed differences in histological appearances and 24·5 per cent of cases were too autolysed to interpret with an increased relative risk of autolysis in a number of large breeds.

ClinicalSignificance:Chronic pancreatitis is a common, under‐estimated disease in the first‐opinion dog population with distinctive breed risks and histological appearances.
Population Genomics and Research Ethics with Socially Identifiable Groups
Authors: McGregor Joan L.
Published: August 2007

The genetic revolution is well underway, with genetic research and knowledge expanding at an exponential rate. Much of the new genetics research is focused on population groups, and proponents of “population genomics” argue that such studies are necessary since genetic “variation” among human populations holds the most promise for technological innovations that can improve human health and lead to increased understanding of the origin of human populations. Population genomic research thus targets specific groups to discover variation that could lead to knowledge about genetic disorders, possible cures, and the origin and migration patterns of distinctive peoples. Research on genetic differences among groups or populations, however, raises many pressing ethical and legal questions. For example, focus on biological differences of racial and ethnic groups has in the past lead to assumptions about superiority and inferiority between groups, and in practice resulted in stigmatization and discrimination. Consequently, attention on groups should raise legal and moral red flags and compel us to move cautiously in this area. Pragmatically, targeting population groups as the object of study requires the determination of the nature and scope of “population groups” for purposes of genetics research.
The Human Genome as Common Heritage: Common Sense or Legal Nonsense?
Authors: Ossorio Pilar N.
Published: August 2007

In the opening years of the 21st century, it became fashionable to describe the human genome as belonging to the common heritage of humanity. The United Nations, in its Universal Declaration on the Human Genome and Human Rights, now identifies the human genome as part of the common heritage, as does the international Human Genome Organization (HUGO) and the Council of Europe. The common heritage concept has played a prominent role in arguments against patenting the human genome or portions thereof. This essay considers whether the common heritage designation will advance the political and legal goals of its proponents.
Informed Consent: Physician Inexperience is a Material Risk for Patients
Authors: Veerapen Richard J.
Published: August 2007

The Canadian law governing informed consent was significantly influenced by the decision of its Supreme Court inReibl v. Hughes, a case that involved a physician’s failure to warn the patient about the risk of stroke after carotid endarterectomy. Even though most Canadian plaintiffs afterReiblhave continued to lose informed consent cases, it is likely that the judgement in this case has significantly influenced the manner in which physicians now approach the discussion of risk while obtaining consent not only in Canada but also in several other jurisdictions.

The development of informed consent law in the United States similarly became one of the drivers for change in physicians’ practices of information disclosure to their patients. The effect ofReiblon clinical practice is an outstanding example of the law’s positive influence on medical practice, especially in protecting patient autonomy during collaborative medical decision-making.
Lactobacilli and Tartrazine as Causative Agents of Red‐Color Spoilage in Cucumber Pickle Products
Authors: Pérez‐Díaz I.M. , Kelling R.E. , Hale S. , Breidt F. , McFeeters R.F.
Published: August 2007

ABSTRACT:  The cucumber pickling industry has sporadically experienced spoilage outbreaks in pickled cucumber products characterized by development of red color on the surface of the fruits. Lactobacillus casei and Lactobacillus paracasei were isolated from 2 outbreaks of this spoilage that occurred about 15 y apart during the last 3 decades. Both organisms were shown to produce this spoilage when inoculated into pickled cucumbers while concomitantly degrading the azo dye tartrazine (FD&C yellow nr 5). This food dye is used as a yellow coloring in the brine cover solutions of commercial pickled cucumber products. The red color does not occur in the absence of tartrazine, nor when turmeric is used as a yellow coloring in the pickles. Addition of sodium benzoate to the brine cover solutions of a pickled cucumber product, more specifically hamburger dill pickles, prevented growth of these lactic acid bacteria and the development of the red spoilage.
Selected Odor Compounds in Cooked Soymilk as Affected by Soybean Materials and Direct Steam Injection
Authors: Yuan S.H. , Chang S.K.C.
Published: August 2007

ABSTRACT:  Soy odor is a major concern in the consumption of soymilk by Western consumers. The objectives of this study were to determine selected soy odor compounds as affected by soybean materials and direct steam injection and to determine if the steam‐injection method affected overall cooked soy aroma of the soymilk and compared to the soymilk cooked by a traditional indirect method. Five varieties of soybeans with or without lipoxygenases were processed by direct‐steam injection for up to 20 min at 100 °C. Eight selected odor compounds were analyzed by gas chromatography after extraction using a solid‐phase micro‐extraction (SPME) method. Hexanal, hexanol, 1‐octen‐3‐ol, 1‐octen‐3‐one, and trans‐2‐nonenal decreased whereas 2‐pentylfuran and trans‐2, trans‐4‐decadienal increased by boiling up to 20 min. The results showed that soybean variety was a significant factor to affect odor compositions. Direct steam injection cooked soymilk resulted in lower odor contents than a traditional indirect cooking method. The advantage of having a low odor composition in the heated soymilk products made from lipoxygenases‐null soybean varieties could be attained by using normal soybean materials with direct steam injection.
Chemical Composition and Antioxidant Activity of Seeds of Different Cultivars of Mungbean
Authors: Anwar F. , Latif S. , Przybylski R. , Sultana B. , Ashraf M.
Published: August 2007

ABSTRACT:  Seeds of 4 cultivars (M‐1, M‐6, NM‐92, and NM‐98) of mungbean [Vigna radiata (L.) Wilczek] were investigated for proximate composition, antioxidant potential, fatty acids, tocopherols, and minerals profiles. Hexane‐extracted seed oil content of the investigated cultivars of mungbeans ranged from 1.20% to 1.56%. Mungbean seeds were found to be a rich source of protein (20.97% to 31.32%). The contents of Fe, Cu, Mg, Na, K, Ca, and Zn were found to be 105.8 to 190.9, 4.8 to 6.3, 48.6 to 51.7, 382.6 to 562.7, 11.6 to 18.8, 359.2 to 482.9, and 24.9 to 47.2 mg/kg, respectively. The mungbean seeds contained linoleic acid in the highest amount, 340.5 to 465.7 mg/100 g of dry seed, followed by palmitic, oleic, linolenic, stearic, and arachidic acids: 278.1 to 401.2, 212.6 to 293.5, 188.7 to 236.8, 135.5 to 168.4, and 22.8 to 24.5 mg/100 g of dry seed, respectively. The seeds were found to be a rich source of tocopherols (α, γ, δ) ranged from 1.1 to 10.1, 60.7 to 80.9, and 4.6 to 11.2 mg/kg, respectively. Methanolic extracts of the seeds of the mungbean cultivars exhibited a good antioxidant activity as determined in terms of measurement of total phenolic contents (TPC) (0.62 to 1.08 g/100 g of dry matter), percent inhibition of peroxidation (49.8% to 89.2%), reducing power (1.19% to 1.45%), and bleaching β‐carotene. The results of the present analytical study revealed these 4 mungbean cultivars to be a potential source of essential fatty acids, antioxidants, minerals and protein, all of which are linked with positive health benefits.
How Do Consumer Attitudes Influence Acceptance of a Novel Wild Blueberry–Soy Product?
Authors: Teh T. , Dougherty M.P. , Camire M.E.
Published: August 2007

ABSTRACT:  Acceptance of healthful foods by consumers is not yet well understood. In this study, 3 formulations of frozen dessert bars were prepared containing both soy and wild blueberries. Soy content was controlled to provide an amount of soy protein that qualified for the health claim for soy and reduced risks for cardiovascular disease. Consumers were asked to complete the Health and Taste Attitude Scales (HTAS) and then evaluate the acceptability of the 3 frozen bar types using a 9‐point hedonic scale. One week after the 1st session, the participants returned. Approximately half were given information to read regarding the health benefits of soy protein, the other participants were given no information. The samples were then presented a 2nd time and labeled with their soy protein content. Changes in hedonic scores between sessions were compared and correlated with HTAS ratings. Nutrition information generally did not affect acceptability scores.
Deviation of type I and type II T cells and its negative effect on hematopoiesis in myelodysplastic syndrome
Authors: WU L. , LI X. , CHANG C. , YING S. , HE Q. , PU Q.
Published: August 2007

Immunemediated hematopoietic suppression has been considered as one of significant pathophysiological changes in less‐advanced myelodysplastic syndrome (MDS). To explore deviation of T cell subsets and its relationship to marrow cells apoptosis, measurement of helper‐T (Th)/cytotoxic‐T (Tc) subsets as well as the deviation situation within this two subsets (Th1/Th2 and Tc1/Tc2) in marrow was performed by flow cytometry from 39 MDS patients and 13 normal controls. Interferon (INF)‐γ and tumor necrosis factor (TNF)‐α in marrow serum was simultaneously detected by ELISA (enzyme‐linked immunosorbent assay). Furthermore, apoptosis rate of marrow cells was demonstrated by TUNEL (TdT‐mediated dUTP nick end labeling). Results showed that Th and Tc subsets were unevenly activated, both deviating to type I response, which was especially obvious in patients with RCMD (according to WHO classification) and in lower‐risk cases defined by International Prognosis Scoring System (IPSS). Level of INF‐γ/TNF‐α in MDS marrow serum was markedly elevated, and so did the apoptosis rate of marrow cells. Although type I deviation was observed both in Th and Tc subsets, just Th1 cell percentage showed positive correlation with level of INF‐γ/TNF‐α and apoptotic index of nucleated cells. In addition, cytokines level in marrow serum presented positive correlation to apoptosis. We then deduced that the increased Th1 cells in marrow may account for nucleated cells apoptosis in MDS through overproduced proapoptotic cytokines such as INF‐γ and TNF‐α. Our results suggested that type I deviation of T cell subsets may play a role in pantocytopenia in MDS and the deviation pattern may be as a direct and effective parameter to predict response of immunosuppression therapy.
Plant Speciation
Authors: Rieseberg Loren H. , Willis John H.
Published: August 2007

Like the formation of animal species, plant speciation is characterized by the evolution of barriers to genetic exchange between previously interbreeding populations. Prezygotic barriers, which impede mating or fertilization between species, typically contribute more to total reproductive isolation in plants than do postzygotic barriers, in which hybrid offspring are selected against. Adaptive divergence in response to ecological factors such as pollinators and habitat commonly drives the evolution of prezygotic barriers, but the evolutionary forces responsible for the development of intrinsic postzygotic barriers are virtually unknown and frequently result in polymorphism of incompatibility factors within species. Polyploid speciation, in which the entire genome is duplicated, is particularly frequent in plants, perhaps because polyploid plants often exhibit ecological differentiation, local dispersal, high fecundity, perennial life history, and self-fertilization or asexual reproduction. Finally, species richness in plants is correlated with many biological and geohistorical factors, most of which increase ecological opportunities.
Observed Flow Compensation Associated with the MOC at 26.5°N in the Atlantic
Authors: Kanzow Torsten , Cunningham Stuart A. , Rayner Darren , Hirschi Joël J.-M. , Johns William E. , Baringer Molly O. , Bryden Harry L. , Beal Lisa M. , Meinen Christopher S. , Marotzke Jochem
Published: August 2007

The Atlantic meridional overturning circulation (MOC), which provides one-quarter of the global meridional heat transport, is composed of a number of separate flow components. How changes in the strength of each of those components may affect that of the others has been unclear because of a lack of adequate data. We continuously observed the MOC at 26.5°N for 1 year using end-point measurements of density, bottom pressure, and ocean currents; cable measurements across the Straits of Florida; and wind stress. The different transport components largely compensate for each other, thus confirming the validity of our monitoring approach. The MOC varied over the period of observation by ±5.7 × 10
6
cubic meters per second, with density-inferred and wind-driven transports contributing equally to it. We find evidence for depth-independent compensation for the wind-driven surface flow.
Temporal Variability of the Atlantic Meridional Overturning Circulation at 26.5°N
Authors: Cunningham Stuart A. , Kanzow Torsten , Rayner Darren , Baringer Molly O. , Johns William E. , Marotzke Jochem , Longworth Hannah R. , Grant Elizabeth M. , Hirschi Joël J.-M. , Beal Lisa M. , Meinen Christopher S. , Bryden Harry L.
Published: August 2007

The vigor of Atlantic meridional overturning circulation (MOC) is thought to be vulnerable to global warming, but its short-term temporal variability is unknown so changes inferred from sparse observations on the decadal time scale of recent climate change are uncertain. We combine continuous measurements of the MOC (beginning in 2004) using the purposefully designed transatlantic Rapid Climate Change array of moored instruments deployed along 26.5°N, with time series of Gulf Stream transport and surface-layer Ekman transport to quantify its intra-annual variability. The year-long average overturning is 18.7 ± 5.6 sverdrups (Sv) (range: 4.0 to 34.9 Sv, where 1 Sv = a flow of ocean water of 10
6
cubic meters per second). Interannual changes in the overturning can be monitored with a resolution of 1.5 Sv.
Human Genome Ultraconserved Elements Are Ultraselected
Authors: Katzman Sol , Kern Andrew D. , Bejerano Gill , Fewell Ginger , Fulton Lucinda , Wilson Richard K. , Salama Sofie R. , Haussler David
Published: August 2007

Ultraconserved elements in the human genome are defined as stretches of at least 200 base pairs of DNA that match identically with corresponding regions in the mouse and rat genomes. Most ultraconserved elements are noncoding and have been evolutionarily conserved since mammal and bird ancestors diverged over 300 million years ago. The reason for this extreme conservation remains a mystery. It has been speculated that they are mutational cold spots or regions where every site is under weak but still detectable negative selection. However, analysis of the derived allele frequency spectrum shows that these regions are in fact under negative selection that is much stronger than that in protein coding genes.
Structure of the Membrane Protein FhaC: A Member of the Omp85-TpsB Transporter Superfamily
Authors: Clantin Bernard , Delattre Anne-Sophie , Rucktooa Prakash , Saint Nathalie , Méli Albano C. , Locht Camille , Jacob-Dubuisson Françoise , Villeret Vincent
Published: August 2007

In Gram-negative bacteria and eukaryotic organelles, β-barrel proteins of the outer membrane protein 85–two-partner secretion B (Omp85-TpsB) superfamily are essential components of protein transport machineries. The TpsB transporter FhaC mediates the secretion of
Bordetella pertussis
filamentous hemagglutinin (FHA). We report the 3.15 Å crystal structure of FhaC. The transporter comprises a 16-stranded β barrel that is occluded by an N-terminal α helix and an extracellular loop and a periplasmic module composed of two aligned polypeptide-transport–associated (POTRA) domains. Functional data reveal that FHA binds to the POTRA 1 domain via its N-terminal domain and likely translocates the adhesin-repeated motifs in an extended hairpin conformation, with folding occurring at the cell surface. General features of the mechanism obtained here are likely to apply throughout the superfamily.
Deep Ultraviolet Light-Emitting Hexagonal Boron Nitride Synthesized at Atmospheric Pressure
Authors: Kubota Yoichi , Watanabe Kenji , Tsuda Osamu , Taniguchi Takashi
Published: August 2007

Materials emitting light in the deep ultraviolet region around 200 nanometers are essential in a wide-range of applications, such as information storage technology, environmental protection, and medical treatment. Hexagonal boron nitride (hBN), which was recently found to be a promising deep ultraviolet light emitter, has traditionally been synthesized under high pressure and at high temperature. We successfully synthesized high-purity hBN crystals at atmospheric pressure by using a nickel-molybdenum solvent. The obtained hBN crystals emitted intense 215-nanometer luminescence at room temperature. This study demonstrates an easier way to grow high-quality hBN crystals, through their liquid-phase deposition on a substrate at atmospheric pressure.
Wittgenstein and the Brain
Authors: Dainton Barry
Published: August 2007

Neuroscience and Philosophy
. Brain, Mind, and Language.
By Maxwell Bennett, Daniel Dennett, Peter Hacker, and John Searle
. Columbia University Press, New York, 2007. 227 pp. $25.50, £16. ISBN 9780231140447.

The authors debate the conceptual foundations of cognitive neuroscience.
Immunogenicity of a Fourth Dose of
Haemophilus influenzae
Type b (Hib) Conjugate Vaccine and Antibody Persistence in Young Children from the United Kingdom Who Were Primed with Acellular or Whole-Cell Pertussis Component-Containing Hib Combinations in Infancy
Authors: Southern Jo , McVernon Jodie , Gelb David , Andrews Nick , Morris Rhonwen , Crowley-Luke Annette , Goldblatt David , Miller Elizabeth
Published: August 2007

In response to the rising incidence of
Haemophilus influenzae
type b (Hib) disease in the United Kingdom, a national campaign to give a booster dose of single-antigen Hib conjugate vaccine to children aged 6 months to 4 years was undertaken in 2003. Children (
n
= 386) eligible for Hib vaccine in the campaign were recruited. Hib antibody concentrations were measured before boost and at 1 month, 6 months, 1 year, and 2 years after boost and were analyzed according to children's ages at booster dose and whether a Hib combination vaccine containing acellular pertussis (aP) or whole-cell pertussis (wP) components was given in infancy. The geometric mean antibody concentrations (GMCs) before the booster declined as the time since primary immunization increased (
P
< 0.001), and GMCs were threefold higher in recipients of wP-Hib than aP-Hib combination vaccines (
P
< 0.001). GMCs 1 month after the booster increased with age (
P
< 0.001) as follows: 6 to 11 months; 30 μg/ml (95% confidence interval [CI], 22 to 40); 12 to 17 months, 68 μg/ml (95% CI, 38 to 124); and 2 to 4 years, 182 μg/ml (151 to 220), with no difference according to the type of priming vaccine received. Antibody levels declined after the booster, but 2 years later, GMCs were more than 1.0 μg/ml for all age groups. By extrapolating data for the decline in antibody levels, we found the GMCs 4 years after boosting were predicted to be 0.6, 1.4, and 2.6 μg/ml for those boosted at 6 to 11 months, 12 to 17 months, and 2 to 4 years, respectively, with levels of at least 0.15 μg/ml in about 90% of individuals. A booster dose of Hib vaccine given after the first year of life should provide long-lasting protection.
Antigenic Polymorphism and Naturally Acquired Antibodies to
Plasmodium vivax
Merozoite Surface Protein 1 in Rural Amazonians
Authors: Bastos Melissa S. , da Silva-Nunes Mônica , Malafronte Rosely S. , Hoffmann Erika Hellena E. , Wunderlich Gerhard , Moraes Sandra L. , Ferreira Marcelo U.
Published: August 2007

Merozoite surface protein 1 of
Plasmodium vivax
(PvMSP-1), a major target for malaria vaccine development, contains six highly polymorphic domains interspersed with conserved sequences. Although there is evidence that the sequence divergence in PvMSP-1 has been maintained over 5 million years by balanced selection exerted by the host's acquired immunity, the variant specificity of naturally acquired antibodies to PvMSP-1 remains poorly investigated. Here, we show that 15 recombinant proteins corresponding to PvMSP-1 variants commonly found in local parasites were poorly recognized by 376 noninfected subjects aged 5 to 90 years exposed to malaria in rural Amazonia; less than one-third of them had detectable immunoglobulin G (IgG) antibodies to at least one variant of blocks 2, 6, and 10 that were expressed, although 54.3% recognized the invariant 19-kDa C-terminal domain PvMSP-1
19
. Although the proportion of responders to PvMSP-1 variants increased substantially during subsequent acute
P. vivax
infections, the specificity of IgG antibodies did not necessarily match the PvMSP-1 variant(s) found in infecting parasites. We discuss the relative contribution of antigenic polymorphism, poor immunogenicity, and original antigenic sin (the skew in the specificity of antibodies elicited by exposure to new antigenic variants due to preexisting variant-specific responses) to the observed patterns of antibody recognition of PvMSP-1. We suggest that antibody responses to the repertoire of variable domains of PvMSP-1 to which subjects are continuously exposed are elicited only after several repeated infections and may require frequent boosting, with clear implications for the development of PvMSP-1-based subunit vaccines.
Multiple-Locus Variable-Number Tandem-Repeat Analysis for Longitudinal Survey of Sources of
Pseudomonas aeruginosa
Infection in Cystic Fibrosis Patients
Authors: Vu-Thien Hoang , Corbineau Gaëlle , Hormigos Katia , Fauroux Brigitte , Corvol Harriet , Clément Annick , Vergnaud Gilles , Pourcel Christine
Published: August 2007

In order to identify the source of infection by
Pseudomonas aeruginosa
in patients with cystic fibrosis (CF), systematic genotyping of isolates is necessary. Multiple-locus variable-number tandem-repeat (VNTR) analysis (MLVA) was used to survey the sources of
P. aeruginosa
infections in a French (Paris, France) pediatric CF center. Between January 2004 and December 2006, 108 patients ages 2 to 21 years who were regularly monitored at the center provided sputum for culture.
P. aeruginosa
was detected in 46 children, 17 of whom had primary colonization. A total of 163 isolates were recovered. MLVA was improved from a previously published method by the addition of new, informative, and easily typeable markers. Upon genotyping with 15 VNTRs, a total of 39 lineages composed of indistinguishable or closely related isolates, were observed. One of them corresponds to “clone C,” which is widely distributed in Europe, and another corresponds to reference strain PA14. Six patients were colonized with two different strains, and the remaining 40 patients were colonized with a single strain. Strains from seven lineages were shared by at least two and up to four patients among a total of 20 patients. The study demonstrates that MLVA is an efficient, easy, and rapid molecular method for epidemiological surveillance for
P. aeruginosa
infection. The resulting data and strain genetic profiles can be queried on
http://bacterial-genotyping.igmors.u-psud.fr
.
Capsule Gene Analysis of Invasive
Haemophilus influenzae
: Accuracy of Serotyping and Prevalence of IS
1016
among Nontypeable Isolates
Authors: Satola Sarah W. , Collins Julie T. , Napier Ruth , Farley Monica M.
Published: August 2007

We evaluated the accuracy of serologic capsule typing by analyzing capsule genes and related markers among invasive
Haemophilus influenzae
isolates before and after the introduction of
H. influenzae
serotype b (Hib) conjugate vaccines. Three hundred and sixty invasive
H. influenzae
isolates were collected as part of Active Bacterial Core surveillance within the Georgia Emerging Infections Program between 1 January 1989 and 31 July 1998. All isolates were biotyped, serotyped by slide agglutination serotyping (SAST), and evaluated using PCR capsule typing. Nontypeable
H. influenzae
(NTHi) isolates were probed with Hib
cap
-gene-containing plasmid pUO38 and with IS
1016
; a subset was examined with phosphoglucose isomerase (
pgi
) genotyping and pulsed-field gel electrophoresis (PFGE). Discrepancies between SAST and PCR capsule typing were found for 64/360 (17.5%) of the isolates; 48 encapsulated by SAST were NTHi by PCR, 8 NTHi by SAST were encapsulated by PCR, 6 encapsulated by SAST were a different capsule type by PCR, and 2 encapsulated by SAST were capsule-deficient Hib variants (Hib-minus). None of the PCR-confirmed NTHi isolates demonstrated homology with residual capsule gene sequences; 19/201 (9.5%) had evidence of IS
1016
, an insertion element associated with division I
H. influenzae
capsule serotypes. The majority of IS
1016
-positive NTHi were biotypes I and V and showed some genetic relatedness by PFGE. In conclusion, PCR capsule typing was more accurate than SAST and Hib-minus variants were rare. IS
1016
was present in 9.5% of NTHi isolates, suggesting that this subset may be more closely related to encapsulated organisms. A better understanding of NTHi may contribute to vaccine development.
Bordetella pertussis
Strains Circulating in Europe in 1999 to 2004 as Determined by Pulsed-Field Gel Electrophoresis
Authors: Hallander Hans , Advani Abdolreza , Riffelmann Marion , von König Carl H. W. , Caro Valerie , Guiso Nicole , Mooi Frits R. , Gzyl Anna , Kaltoft Margit S. , Fry Norman K. , Mertsola Jussi , He Qiushui
Published: August 2007

Clinical isolates of
Bordetella pertussis
collected during the year 2004 (
n
= 153) in eight European countries, Denmark, Finland, France, Germany, The Netherlands, Poland, Sweden, and United Kingdom, were analyzed by pulsed-field gel electrophoresis (PFGE), and their PFGE profiles were compared with those of isolates collected in 1999 (
n
= 102). The 255 isolates produced 59 distinct PFGE profiles. Among the 153 isolates from 2004, 36 profiles were found, while within the 102 isolates from 1999, 33 profiles were detected. One PFGE profile, BpSR11, was dominant (30% to 50%) in all countries except Denmark (10%) and Poland (0%). In comparison with 1999, there was an increase in BpSR11 prevalence in Finland in 2004 from 5% to 40%, coinciding with a major incidence peak. Some other PFGE profiles seemed to be associated with limited dissemination. Poland was the only country in which the most common actual European PFGE profiles were not found. In a dendrogram analysis, all common PFGE profiles were identified within PFGE group IV, and BpSR11 clustered together with PFGE subgroup IVβ. Compared to the 1999 isolates, PFGE group V representative for pertactin variant
prn3
strains had disappeared, and a new cluster was seen. In conclusion, some PFGE profiles, such as BpSR11, evidently have a higher capacity to spread, suggesting increased fitness to the present immunological environment. It is therefore of major interest to continue with surveillance programs of
B. pertussis
isolates, as both waning vaccine-derived immunity and strain variation may play a role in the persistence of pertussis.
Large-Scale Human Immunodeficiency Virus Rapid Test Evaluation in a Low-Prevalence Ugandan Blood Bank Population
Authors: Eller Leigh A. , Eller Michael A. , Ouma Benson J. , Kataaha Peter , Bagaya Bernard S. , Olemukan Robert L. , Erima Simon , Kawala Lilian , de Souza Mark S. , Kibuuka Hannah , Wabwire-Mangen Fred , Peel Sheila A. , O'Connell Robert J. , Robb Merlin L. , Michael Nelson L.
Published: August 2007

The use of rapid tests for human immunodeficiency virus (HIV) has become standard in HIV testing algorithms employed in resource-limited settings. We report an extensive HIV rapid test validation study conducted among Ugandan blood bank donors at low risk for HIV infection. The operational characteristics of four readily available commercial HIV rapid test kits were first determined with 940 donor samples and were used to select a serial testing algorithm. Uni-Gold Recombigen HIV was used as the screening test, followed by HIV-1/2 STAT-PAK for reactive samples. OraQuick HIV-1 testing was performed if the first two test results were discordant. This algorithm was then tested with 5,252 blood donor samples, and the results were compared to those of enzyme immunoassays (EIAs) and Western blotting. The unadjusted algorithm sensitivity and specificity were 98.6 and 99.9%, respectively. The adjusted sensitivity and specificity were 100 and 99.96%, respectively. This HIV testing algorithm is a suitable alternative to EIAs and Western blotting for Ugandan blood donors.
Validation of Nasopharyngeal Sampling and Culture Techniques for Detection of
Streptococcus pneumoniae
in Children in Kenya
Authors: Abdullahi Osman , Wanjiru Eva , Musyimi Robert , Glass Nina , Scott J. Anthony G.
Published: August 2007

We compared nasopharyngeal swabs against nasal wash cultures for detecting colonizing pneumococci and examined the effect of frozen storage in skim milk-tryptone-glucose-glycerin on culture. Among the 55 children with positive nasal wash cultures, swab cultures were positive for 47 (85%). Of the 96 swabs positive on direct plating, 94 (98%) were positive when recultured after freezing.
Evaluation of Pan-Dermatophyte Nested PCR in Diagnosis of Onychomycosis
Authors: Garg Jaya , Tilak Ragini , Singh Sanjay , Gulati Anil Kumar , Garg Atul , Prakash Pradyot , Nath Gopal
Published: August 2007

In this study, nested PCR using novel primers targeting the pan-dermatophyte-specific sequence of the chitin synthase 1 gene (
CHS1
) was compared with KOH microscopy, culture isolation, and single-round PCR for diagnosis of 152 patients with clinically suspected onychomycosis. Results indicate that nested PCR may be considered the gold standard for the diagnosis of cases of onychomycosis for which the etiological agents are dermatophytes.