bluuebunny/crossref_metadata_2025 huggingface dataset:
Vicia faba germplasm multiplication – floral traits associated with pollen‐mediated gene flow under diverse between‐plot isolation strategies
Authors: Suso M.J. , Nadal S. , Roman B. , Gilsanz S.
Published: November 2007

Contamination, by pollen, from neighbouring accessions is a risk during Vicia faba seed stock multiplication. In insect‐pollinated plants, floral traits are expected to play an important role determining pollen‐mediated gene flow variation. The aim of this study was to identify floral traits associated with interplot gene flow that could be used as effective predictors of gene flow potential to improve between‐plot isolation strategies in the field for seed multiplication. The isolation strategies tested were a barren zone, two trap crops, a faba bean male sterile variety and a tetraploid genotype and a non‐pollinated crop, a Vicia narbonensis population. Four genotypes, fixed for alternative isozyme alleles allowed identification of between‐plot hybrids through progeny testing. G‐test was used to analyse the independence of isolation zone and genotype. Principal component analysis was used to obtain information on the usefulness of faba bean traps as barriers to prevent interplot gene flow. Paternity analysis in conjunction with multiple regression allowed the determination of floral traits that accounted for the largest proportion of variation in pollen‐mediated gene flow across each of the four isolation strategies. The floral traits studied were grouped into functional categories and were used as independent variables with gene flow as the dependent variable in a forward stepwise multiple regression procedure. There were large variations in gene flow level and patterns among the genotypes. It was shown that gene flow was isolation zone and genotype dependent. Multivariate regression models showed that differences in floral traits accounted for more than 70% of the variation in interplot gene flow. The relative importance of various floral traits depends on the isolation zone. Flower advertisement appeared important in predicting gene flow in plots surrounded by a barren zone. With regard to plots surrounded by a V. narbonensis population, the role of a reward trait, pollen production, was established. In contrast, in plots surrounded by faba bean trap crops, ovary length played the most important and consistent role in accounting for variation in gene flow. Our results show that interplot gene flow is largely dependent on floral traits, and thus confirm the utility of floral traits for generating hypotheses about cultivar outcrossing or inbreeding behaviour. Thus, it could help to devise more efficient procedures for seed multiplication.
Sevelamer Hydrochloride Improves Hyperphosphatemia in Hemodialysis Patients With Low Bone Turnover Rate and Low Intact Parathyroid Hormone Levels
Authors: Kokuho Toshiharu , Toya Yoshiyuki , Kawaguchi Yoshiaki , Tamura Koichi , Iwatsubo Kousaku , Dobashi Yasushi , Nakazawa Akiko , Takeda Hideyuki , Iwatsubo Mizuka , Hirawa Nobuhito , Yasuda Gen , Ohnishi Toshimasa , Umemura Satoshi
Published: November 2007

Abstract:  Sevelamer improves hyperphosphatemia without increasing the calcium load. However, it remains unknown whether sevelamer restores bone metabolism in hemodialysis patients with low bone turnover osteodystrophy and hypoparathyroidism. We investigated the changes in serum intact parathyroid hormone (iPTH) and bone metabolic marker levels after replacing calcium carbonate with sevelamer in these patients. We also conducted stratified analysis based on patient background and multivariate analysis to determine the factors affecting these parameters. During sevelamer replacement therapy, serum calcium and phosphate concentrations, and the calcium phosphate product were measured at 0, 1, 3, and 6 months. Serum iPTH, bone alkaline phosphatase and osteocalcin concentrations were measured at 0 and 6 months. In hemodialysis patients (71 men and 46 women, 63 ± 12 years old) serum calcium levels and the calcium phosphate product decreased significantly at 1 month. Serum iPTH, bone alkaline phosphatase and osteocalcin levels increased significantly at 6 months. Increases in serum iPTH concentrations were observed in all stratified groups. Significant increases in serum bone alkaline phosphatase and osteocalcin concentrations were found only in the relative hypoparathyroidism group (iPTH levels ≥51.5 pg/mL, the median pretreatment level). Multivariate analysis showed that the factors affecting change in serum iPTH level are baseline serum iPTH, baseline calcium level (≥9.5 mg/dL), and dialysis duration of 10 years or longer. Sevelamer appears useful for the treatment of hyperphosphatemia in these patients. Particularly, in the relative hypoparathyroidism group, the iPTH secretory response is probably enhanced and bone turnover may have been improved as a result of reducing the calcium load.
Subscores Based on Classical Test Theory: To Report or Not to Report
Authors: Sinharay Sandip , Haberman Shelby , Puhan Gautam
Published: November 2007

There is an increasing interest in reporting subscores, both at examinee level and at aggregate levels. However, it is important to ensure reasonable subscore performance in terms of high reliability and validity to minimize incorrect instructional and remediation decisions. This article employs a statistical measure based on classical test theory that is conceptually similar to the test reliability measure and can be used to determine when subscores have any added value over total scores. The usefulness of subscores is examined both at the level of the examinees and at the level of the institutions that the examinees belong to. The suggested approach is applied to two data sets from a basic skills test. The results provide little support in favor of reporting subscores for either examinees or institutions for the tests studied here.
DETERMINATION OF HEAT TRANSFER COEFFICIENT IN COOLING‐FREEZING TUNNELS USING EXPERIMENTAL TIME–TEMPERATURE DATA
Authors: SANTOS C.A. , CARCIOFI B.A.M. , DANNENHAUER C.E. , HENSE H. , LAURINDO J.B.
Published: November 2007

In industrial freezing tunnels, knowledge of the spatial distribution of convective heat transfer (h) is crucial in predicting process times. The objective of this study was to develop an appropriate and simple methodology to determine the spatial distribution of h values inside tunnels. A dedicated device, consisting of a rectangular metal tank filled with an alcoholic solution, with a temperature sensor inserted in its interior, was used as a model system. The transient temperatures of the system (tank solution) were used to calculate h values at different positions inside the tunnels. The main result of this paper is the experimental method itself, which is a reproducible and reliable procedure for determining heat transfer coefficients inside industrial tunnels. The method is sensitive enough to determine spatial heterogeneities and is versatile with respect to the system geometry, which makes it a useful and simple tool to carry out diagnostic tests in industrial plants.

PRACTICAL APPLICATIONS

In cooling/freezing tunnels, it is important to have convective heat transfer conditions that are spatially homogeneous, leading to homogeneous cooling/freezing processes. This is not obvious in industrial tunnels because of the arrangement of packages and fan positions. Tunnel operational conditions and layout lead to a specific airflow pattern, creating zones of high and low air flux that leads to zones of high and low convective heat transfer (h) values. This is the case for industrial tunnels used to freeze pack poultry cuts. The method proposed in this work is a useful tool to detect h value heterogeneities and to determine the average h value of preexisting tunnels. Such diagnoses can support decisions regarding layout changes or changes in the amount and positions of the fans in a tunnel. Computational fluid dynamics can also be used, but this provides more realistic data if actual h values are used.
MODELING VARIETAL EFFECT ON THE WATER UPTAKE BEHAVIOR OF MILLED RICE (ORYZA SATIVA L.) DURING SOAKING
Authors: YADAV B.K. , JINDAL V.K.
Published: November 2007

Milled rice is soaked until saturation before cooking and other processing. The soaking behavior of the milled rice is affected by varietal factor as well as initial moisture content (M0) of the samples. In the present study, tests were performed for milled whole kernels of 10 rice varieties ranging from low to high amylose content (16–29% d.b.) with three initial moisture levels (approximately 8, 12 and 16% d.b.) for monitoring water uptake in rice kernels during soaking at room temperature (25 ± 1C), in relation to the varietal differences manifested by the physicochemical properties. The water uptake by milled rice kernels took place at a faster rate in the beginning and was followed by a diminishing rate finally leading to a saturated value during soaking. The water uptake of the kernels during soaking could be best expressed by a modified exponential relationship with R2 values ranging from 0.971 to 0.998 for all varieties. The slope of the fitted straight line between actual and estimated moisture contents of milled rice during soaking using a modified exponential relationship was about unity (0.998) with a high R2 value of 0.989 and a root mean square error of 1.2% d.b. The parameters of the fitted model were the function of the M0 and the physicochemical properties of the milled rice. Using developed relationship, the water uptake of the milled rice during soaking could be estimated from its M0 and the physicochemical properties within±10% of the actual values.

PRACTICAL APPLICATIONS

This information would be useful for the scientific world working on the soaking characteristics of various varieties of rice, mainly for the modeling of the soaking process. It could also be used as a tool in selecting the rice varieties to meet their desired water uptake properties in relation to their psychochemical properties by rice breeder scientists.
Research Article: Comparative Molecular Field Analysis of Quinoline Derivatives as Selective and Noncompetitive mGluR1 Antagonists
Authors: Nataraja Sekhar Y. , Ravi Shashi Nayana M. , Ravikumar Muttineni , Mahmood S.k.
Published: November 2007

A 3D‐ QSAR model os Comparative Molecular Field Analysib (CoMFA) of 45 quinoline derivatives as metaborropic glutamate receptor subtype 1 (mGluR1) inhibitors wew investigated. The CoMFA analysis provided a model withq2value of 0.827 andr2value of 0.990, in whichq2value of 0.827 and anr2value of 0.990, in which the good correlation between the inhibitory activities and the steric and electrostatic molecular field around the analoques was observed. The predictive ability of the models was validated using the set of 12 compounds that were not included in the training set of 33 compounds. These results provided further understanding of the relationship between the structural features of quinolone derivatives and its activities, which should be applicable to design and find new potential mGluR1 inhibitors.
Magic and Divination in Ancient Israel
Authors: Jeffers Ann
Published: November 2007

Despite officially condemning all magicians and divinatory practitioners, the Old Testament/Hebrew scriptures is replete with references to magic and divination. In an attempt to map out and understand the great variety of divinatory practices in the Old Testament/Hebrew Bible from techniques as varied as astrology, lot casting, necromancy or hepatoscopy to cite only a few, this article will re‐examine the concept of ‘magic’ and re‐evaluate the ways in which the Western world, especially since the nineteenth century, has viewed ‘magic’ as part of a series of dichotomies: religion vs. magic, science vs. magic; ‘magic’ is even seen as part of gender divisions (magic/women vs. religion/men). ‘Emic’ and ‘etic’ categories are also examined and a new definition situating magic as an ‘emic’ category is proposed: magic and divination are part of a complex system of religious intermediation where all the components of the cosmos interrelate. In this regard, ancient Israel shares the same worldview as its ancient Near Eastern neighbours and in particular a belief in cosmic forces originating and controlled by the dominant deity or deities. While the rational underpinning of such practices are examined (and questions about control and gender touched upon), it is also argued that a proper understanding of magic and divination in ancient Israel can only be viewed as an integral part of its cosmology. An ‘emic’ definition of magic suggests its connection with Torah and wisdom.
Interpreting Magic and Divination in the Ancient Near East
Authors: Jeffers Ann
Published: November 2007

This article examines the problems raised by traditional definitions of magic and divination and re‐evaluates the ways in which the Western world, especially since the nineteenth century, has viewed ‘magic’ as part of a series of dichotomies: religion vs. magic, science vs. magic. Main highlights and contributions to the search for a better understanding of magic include the works of Frazer, Malinowski, and Huber & Mauss. The recent input of multi‐disciplinary approaches, for example, sociology and anthropology, while being important and helpful, in particular by highlighting the importance of context, also requires careful handling: the reader must be weary of the ideology of the observer, which often reflects a Western tendency to ‘classify’ rather than the views of the observed. Magic and divination need to be evaluated differently in the same space at different times and so it is important for any meaningful discussion to take place to focus on one specific culture and its worldview. Examples from the ancient Near Eastern world, that is, Egypt with its concept of Heka, and Mesopotamia will be used in order to search for a new conceptual framework to view magic and divination. It is suggested that terminology and cosmology give an entry point into a complex system of religious intermediation, in which belief in cosmic forces originating and controlled by the dominant deity or deities prevails. Magic and divination can only be understood as an integrated part of this framework.
Project English: Lessons From Curriculum Reform Past
Authors: O’Neil Wayne
Published: November 2007

Project English was born in 1962, a late addition to the curriculum reform movement in the USA that grew out of the Cold War race to dominate outer space. The Oregon Curriculum Study Center, one of the initial 12 Project English centers, took as its goal the complete reformation of the secondary‐school language arts curriculum and the education of its teachers. During its 6‐year run, the Oregon Curriculum Study Center produced a new secondary‐school curriculum in grammar, rhetoric, and literature, the result of collaborative work between the teachers in the field and members of the University of Oregon English Department. Examining the Oregon Curriculum Study Center's work on the grammar component of the curriculum, this article describes the pedagogical (Socratic) and theoretical (transformational) bases of this component, its content, and its development, and offers some lessons to be learned in the context of explaining why this attempt to replace the old grammar with a new one ultimately failed, the result of both internal contradictions and of external forces beyond the Oregon Curriculum Study Center's control.
Influenza‐associated hospitalization in urban Thai children
Authors: Suntarattiwong Piyarat , Sian‐nork Chotip , Thongtipa Parada , Thawatsupha Pranee , Kitphati Rungreung , Chotpitayasunondh Tawee
Published: November 2007

Background  Studies in North America and Europe have shown that young children are at increased risk of serious complications and hospitalization from influenza infection. In Thailand, however, influenza is commonly considered a mild infection that rarely requires hospitalization. An improved understanding of the burden of serious complications from influenza infection in young children is needed to inform clinical treatment and vaccination guidelines.

Methods  We conducted a prospective study of children 0–5 years of age with lower respiratory tract infection or influenza‐like illness admitted to a pediatric tertiary‐care hospital in Bangkok, Thailand during July 2004 to July 2005. All respiratory specimens were tested for influenza using a rapid antigen test and tissue cell culture.

Results  Thirty‐nine of 456 (8.6%) hospitalized children had culture‐positive influenza. Eighty percent of hospitalized influenza patients had no underlying chronic illnesses. Nineteen (49%) influenza patients required hospital stays of 5 days or more and two patients required mechanical ventilation. Influenza activity demonstrated bimodal seasonal variation with peak activity from August to October and January to April. Cough was present in 38 (97%) cases and fever >38.5°C was significantly associated with influenza.

Conclusion  Influenza is an important cause of hospitalization in children <5 years of age in Thailand. Children <5 years should be considered as a target group when establishing clinical guidelines for antiviral treatment and influenza vaccination.
Suggested Interpretation of Polysulfone Dosemeter Mathematical Response
Authors: Colucci Marcello
Published: November 2007

An interpretation of mathematical response of polysulfone film dosemeters, proposed in the literature, is suggested, considering the photochemical reaction of degradation, which a polymer film undergoes when exposed to UV radiation. The function is interpreted using a highly simplified model of photo‐degradation. The interpretation is aimed to stimulate further reflections on the possibility of modeling exactly the behavior of the polymer film, in order to obtain an exact calibration curve, based on physico‐chemical considerations, rather than on pure empirical experience.

We show that the simplified reaction scheme leads to a kinetic model described by a linear system of differential equations, which is the key aspect of the response function interpretation. The linearization is a consequence of the schematization employed, which although simple, is truly reasonable and already proposed also by other authors.
Effects of the Interaction Between β‐Carboline‐3‐carboxylic acid N‐Methylamide and Polynucleotides on Singlet Oxygen Quantum Yield and DNA Oxidative Damage
Authors: García‐Zubiri Iñigo X. , Burrows Hugh D. , Sérgio Seixas de Melo J. , Pina Joao , Monteserín María , Tapia María J.
Published: November 2007

The complexation of β‐carboline‐3‐carboxylic acid N‐methylamide (βCMAM) with the sodium salts of the nucleotides polyadenylic (Poly A), polycytidylic (Poly C), polyguanylic (Poly G), polythymidylic (Poly T) and polyuridylic (Poly U) acids, and with double stranded (dsDNA) and single stranded deoxyribonucleic acids (ssDNA) was studied at pH 4, 6 and 9. Predominant 1:1 complex formation is indicated from Job plots. Association constants were determined using the Benesi–Hildebrand equation. βCMAM‐sensitized singlet oxygen quantum yields were determined at pH 4, 6 and 9, and the effects on this of adding oligonucleotides, dsDNA and ssDNA were studied at the three pH values. With dsDNA, the effect on βCMAM triplet state formation was also determined through triplet–triplet transient absorption spectra. To evaluate possible oxidative damage of DNA following singlet oxygen βCMAM photosensitization, we used thiobarbituric acid‐reactivity assays and electrophoretic separation of DNA assays. The results showed no oxidative damage at the level of DNA degradation or strand break.
UV‐induced Degradation of Collagen I Is Mediated by Soluble Factors Released from Keratinocytes†
Authors: Yarosh Daniel , Dong Kelly , Smiles Kenneth
Published: November 2007

Photoaging is a complex condition but its hallmark is the destruction of dermal collagen. This has been attributed to the direct activation of fibroblast matrix metalloproteinases by solar UV. However, we report here that unirradiated fibroblasts increase metalloproteinase production and digest collagen when exposed to cell culture media from irradiated keratinocytes. Enhanced DNA repair in the keratinocytes ameliorates this response. This suggests that soluble factors induced by DNA damage in UV‐exposed epidermal keratinocytes signal collagen degradation by fibroblasts in the dermis. This motif of DNA damage in keratinocytes producing effects on other cell types mediated by soluble factors was first identified by Kripke and colleagues in studying UV‐induced immune suppression.
Accumulation and Interaction of Hypericin in Low‐density Lipoprotein— A Photophysical Study
Authors: Mukherjee Prasun , Adhikary Ramkrishna , Halder Mintu , Petrich Jacob W. , Miskovsky Pavol
Published: November 2007

The accumulation and interaction of hypericin with the biologically important macromolecule, low‐density lipoprotein (LDL), is investigated using various steady‐state and time‐resolved fluorescence measurements. It is concluded that multiple hypericins can penetrate considerably deeply into the LDL molecule. Up to ∼20 nonaggregated hypericin molecules can enter LDL; but upon increasing the hypericin concentration, the fluorescence lifetime of hypericin decreases drastically, suggesting most likely the self‐quenching of aggregated hypericin. There is also evidence of energy transfer from tryptophans of the constituent protein, apoB‐100, to hypericin in LDL. The results demonstrate the ability of LDL to solubilize hypericin (a known photosensitizer) in nonaggregated form, which has implications for the construction of drug delivery systems.
Ultraviolet‐A and ‐B Differentially Modify the Tyrosine‐Kinase Profile of Human Keratinocytes and Induce the Expression of Arg†
Authors: Klosner Gabriele , Varecka Roland , Knobler Robert , Trautinger Franz
Published: November 2007

To investigate the expression profile of protein tyrosine kinases (PTKs) in normal human epidermal keratinocytes (NHEK) in response to UVA and UVB we employed a reversed transcriptase polymerase chain reaction (PCR) approach using degenerate primers derived from the conserved catalytic domain of PTKs. Quantitative real‐time PCR with specific primers was used to confirm the influence of UV on the expression of the identified PTKs. Arg (Abelson‐related gene, Abl2) was the PTK with the highest prevalence (30% of all PTKs) and UVA led to a further induction of Arg expression reaching nine‐fold mRNA baseline expression at 17 h after irradiation. UVB was followed by an initial downregulation and a subsequent increase in Arg mRNA reaching five‐fold baseline levels after 24 h. We conclude that UVA and UVB differentially modify the expression of PTKs in NHEK, and that Arg appears to have a major role in the response of keratinocytes to UV. These results provide a basis for further studies of PTK in UV‐induced signaling that regulates protective responses, cell growth and carcinogenesis in the skin.
Spectrophotometric Methods for Quantifying Pigmentation in Human Hair—Influence of MC1R Genotype and Environment
Authors: Shekar Sri N. , Duffy David L. , Frudakis Tony , Montgomery Grant W. , James Michael R. , Sturm Richard A. , Martin Nicholas G.
Published: November 2007

Eumelanin (brown/black melanin) and pheomelanin (red/yellow melanin) in human hair can be quantified using chemical methods or approximated using spectrophotometric methods. Chemical methods consume greater resources, making them less attractive for epidemiological studies. This investigation sought to identify the spectrophotometric measures that best explain the light–dark continuum of hair color and the measure that is best able to distinguish red hair from nonred hair. Genetic analysis was performed on these two measures to determine the proportion of genetic and environmental influences on variation in these traits. Reflectance curves along the visible spectrum and subjective ratings of hair color were collected from 1730 adolescent twin individuals. Discriminant class analyses were performed to determine the spectrophotometric measure that could best proxy for eumelanin and pheomelanin quantities. The ratio of light reflected in the green portion of the spectrum to that reflected in the red portion of the spectrum was best able to distinguish red hair from nonred hair. Melanocortin 1 receptor (MC1R) genotype explained some, but not all, variation in this measure. Light absorbed in the red portion of the spectrum was best able to explain the light–dark continuum of hair color. Variance components analysis showed that there were qualitatively different genetic influences between males and females for the light–dark continuum of hair. Our results show that spectrophotometric measures approximating variation in eumelanin and pheomelanin may be considered as an alternative to chemical methods in larger epidemiological studies.
Chemistry of Mixed Melanogenesis—Pivotal Roles of Dopaquinone†
Authors: Ito Shosuke , Wakamatsu Kazumasa
Published: November 2007

Melanins can be classified into two major groups—insoluble brown to black pigments termed eumelanin and alkali‐soluble yellow to reddish‐brown pigments termed pheomelanin. Both types of pigment derive from the common precursor dopaquinone (ortho‐quinone of 3,4‐dihydroxyphenylalanine) which is formedviathe oxidation ofl‐tyrosine by the melanogenic enzyme tyrosinase. Dopaquinone is a highly reactiveortho‐quinone that plays pivotal roles in thechemicalcontrol of melanogenesis. In the absence of sulfhydryl compounds, dopaquinone undergoes intramolecular cyclization to form cyclodopa, which is then rapidly oxidized by a redox reaction with dopaquinone to give dopachrome (and dopa). Dopachrome then gradually and spontaneously rearranges to form 5,6‐dihydroxyindole and to a lesser extent 5,6‐dihydroxyindole‐2‐carboxylic acid, the ratio of which is determined by a distinct melanogenic enzyme termed dopachrome tautomerase (tyrosinase‐related protein‐2). Oxidation and subsequent polymerization of these dihydroxyindoles leads to the production of eumelanin. However, when cysteine is present, this process gives rise preferentially to the production of cysteinyldopa isomers. Cysteinyldopas are subsequently oxidized through redox reaction with dopaquinone to form cysteinyldopaquinones that eventually lead to the production of pheomelanin. Pulse radiolysis studies of early stages of melanogenesis (involving dopaquinone and cysteine) indicate that mixed melanogenesis proceeds in three distinct stages—the initial production of cysteinyldopas, followed by their oxidation to produce pheomelanin, followed finally by the production of eumelanin. Based on these data, a casing model of mixed melanogenesis is proposed in which a preformed pheomelanic core is covered by a eumelanic surface.
Strontium Isotope Analysis of Kimberlitic Groundmass Perovskite via LA‐MC‐ICP‐MS
Authors: Paton Chad , Woodhead Jon D. , Hergt Janet M. , Phillips David , Shee Simon
Published: November 2007

Strontium isotopic composition is a potentially powerful tracer in studies of kimberlitic rocks but the results from even the most carefully collected and stringently prepared bulk‐rock samples are still hampered by contamination and alteration effects. Here we describe a LA‐MC‐ICP‐MS technique which can obtain accurate, high precision Sri ratios from 50–150 μm kimberlitic groundmass perovskite without requiring time‐consuming mineral separation procedures. Since perovskite is a robust magmatic phase with an extremely low Rb/Sr ratio, the effects of late‐stage crustal contamination, post‐emplacement alteration and age correction are minimised and results are more representative of primary melt compositions, while additionally preserving powerful grain‐scale spatial and textural information. We demonstrate that the adopted protocol overcomes isobaric interferences from Kr+, Rb+, Er2+ and Yb2+, and that Ca dimers and Ca argides do not detectably affect the quality of 87Sr/86Sr ratios produced. To illustrate the utility of the technique, contrasting bulk‐rock and in situ perovskite results from eleven Proterozoic kimberlites are documented.
Increase of granzyme B‐positive cells in ascitic fluid of patients with spontaneous bacterial peritonitis
Authors: Perrella Alessandro , Grattacaso Stella , Gnarini Maria Rosaria , D'Antonio Anna , Sbreglia Costanza , Atripaldi Luigi , Conti Pio , Perrella Oreste
Published: November 2007

Spontaneous bacterial peritonitis (SBP) occurs as a direct consequence of bacteria entering ascitic fluid (AF) from the intestinal lumen trough in several ways, including the hematogenous and mesenteric lymph nodes route. There are few studies on the cytokine profile of ascitic‐derived mononuclear cells of patients with SBP, particularly on granzyme B (GZB). The aim of the present study was to verify whether patients with SBP have GZB‐positive cells, whether they are increased in patients with aseptic ascites, and their trend after antibiotic treatment. We enrolled 36 consecutive patients (24 males and 12 females) with SBP on histologically‐proven hepatitis C virus cirrhosis (group A) and 20 patients (11 males and nine females with ascites, but without evidences of SBP (group B). The diagnosis of SBP was made according to the following criteria: positive colture in AF or blood (at least two cultures) and neutrophils in AF (>250 mL polymorphonuclear leukocytes). For these patients we used ELISpot to assay GZB production on purified mononuclear cells in ascitesand peripheral blood, coupled with tumor necrosis factor‐α tested using ELISA. A non‐parametric statistical analysis was used to assess significant differences and correlations. We found positive culture in all of the patients with SBP (80% Escherichia coli; 20% Enterococcus faecium). Furthermore, the patients in group A had a higher number of GZB spot‐forming colonies than the patients in group B (P < 0.001). GZB‐positive cells were lower in the peripheral blood than those found in the AF of patients with SBP, while no differences were found between blood and AF in group B. Furthermore, after antibiotic treatment, GZB was reduced in the patients with SBP (P < 0.05). In conclusion, GZB may be an important mediator of the immune response towards bacteria in AF and could be used as a diagnostic tool.
Evidence of oxidative stress as a cofactor in the development of insulin resistance in patients with chronic hepatitis C
Authors: Mitsuyoshi Hironori , Itoh Yoshito , Sumida Yoshio , Minami Masahito , Yasui Kouichirou , Nakashima Toshiaki , Okanoue Takeshi
Published: November 2007

Aim:  The mechanisms by which metabolic disorders develop in patients with chronic hepatitis C are unknown. Our study aimed to test whether oxidative stress contributes to these mechanisms.

Methods:  The index of homeostasis model assessment–insulin resistance (HOMA–IR) and serum and hepatic levels of thioredoxin (Trx), which are markers of oxidative stress, were evaluated in 203 biopsy‐proven chronic hepatitis C patients with hepatitis C virus (HCV) genotype 1 or 2 infection. HOMA–IR and Trx levels were compared with baseline values after phlebotomy in 23 patients.

Results:  HOMA–IR and serum Trx levels were significantly correlated with disease stage (HOMA–IR, P < 0.00001; Trx, P < 0.0001) and independently predicted fibrosis scores (HOMA–IR, P < 0.05; Trx, P < 0.005). Steatosis (%) was significantly correlated with HOMA–IR (P < 0.00005) and Trx (P < 0.001) stage (P < 0.00001). Serum Trx levels were significantly correlated with HOMA–IR (P < 0.05), even after adjustment for body mass index (P < 0.05). Furthermore, the mRNA levels of hepatic Trx were significantly correlated with HOMA–IR (P < 0.05) and independently‐predicted HOMA–IR (P < 0.05). The alanine aminotransferase (P < 0.00001), Trx (P < 0.05), and HOMA–IR (P < 0.05) serum levels decreased significantly after phlebotomy; these effects were similar even in non‐responders to interferon.

Conclusion:  Oxidative stress contributed to the development of IR irrespective of obesity in patients with HCV genotype 1 or 2 infection. This study could contribute to our understanding of how metabolic disorders develop and how they should be treated in chronic hepatitis C patients.
Intrahepatic status of regulatory T cells in autoimmune liver diseases and chronic viral hepatitis
Authors: Sakaki Masashi , Hiroishi Kazumasa , Baba Toshiyuki , Ito Takayoshi , Hirayama Yuichi , Saito Koji , Tonoike Takahiko , Kushima Miki , Imawari Michio
Published: November 2007

Aim:  Regulatory T cells (Tregs) maintain immunological tolerance and suppress autoreactive immune responses. We evaluated the intrahepatic status of Tregs in patients with autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), chronic hepatitis C (CH‐C), or chronic hepatitis B (CH‐B).

Methods:  We analyzed 85 patients (20 AIH, 22 PBC, 27 CH‐C, and 16 CH‐B) and 14 controls. Using liver tissue samples obtained by needle biopsy or from marginal parts of resected metastatic liver tumors in the controls, immunohistochemical analyses of forkhead box P3+, which is a specific marker for Tregs, CD4+, and CD8+ cells were performed.

Results:  Intrahepatic Tregs were significantly more infiltrated in patients with liver diseases than in the controls. There were significantly fewer intrahepatic Tregs in the AIH patients than in the PBC patients (P = 0.037). Patients with alow frequency of intrahepatic Tregs were detected significantly more in the AIH and CH‐B groups than in the PBC and CH‐C groups (P < 0.05). In addition, the frequency of Tregs decreased in the liver of PBC patients as the pathological stage of the disease advanced. We found significantly less infiltration of CD4+ T cells in AIH than in other diseases (P < 0.05). Liver‐infiltrating CD8+ T cells were detected more frequently in the CH‐B group than in other groups (P < 0.003).

Conclusion:  Intrahepatic Tregs were increased in both patients with autoimmune liver diseases and those with viral hepatitis. In autoimmune liver diseases, intrahepatic Tregs were fewer in the AIH patients than in the PBC patients.
Assessment of nutritional status of patients with hepatitis C virus‐related liver cirrhosis
Authors: Kawabe Naoto , Hashimoto Senju , Harata Masao , Nitta Yoshifumi , Murao Michihito , Nakano Takuji , Shimazaki Hiroaki , Kobayashi Kyoko , Komura Naruomi , Ito Hiroko , Niwa Asako , Narita Wakana , Hanashita Junko , Ikeda Ayako , Yoshioka Kentaro
Published: November 2007

Aim:  Nutrition support for patients with liver cirrhosis, such as late evening snacks and branched‐chain amino acids, has been demonstrated to be effective. However, the assessment of the malnutrition of liver cirrhosis is still a problem. The aim of this study was to assess the nutritional status of patients with liver cirrhosis due to hepatitis C virus by six methods and to test the sensitivity and specificity of these methods.

Methods:  In total, 86 patients with liver cirrhosis due to hepatitis C virus were assessed for nutritional status by triceps skinfold thickness (TSF), arm muscle circumference (AMC), subjective global assessment (SGA), nutritional risk index (NRI), Maastricht index (MI), and instant nutritional assessment (INA).

Results:  Malnutrition was found in 11 (12.8%) patients by TSF, 15 (17.4%) by AMC, 22 (25.6%) by SGA, 52 (60.5%) by the NRI, 66 (76.7%) by the MI, and in 54 (62.8%) by INA. The MI detected malnutrition at a significantly higher rate compared with the other five methods. Sixty‐two patients were diagnosed as malnourished by the combined index, which defines the patients as malnourished when any two of the NRI, MI, and INA also define them as malnourished. The misclassification rate compared with the combined indexes was significantly lower in the MI (4.7%) than in any of the TSF (59.3%), AMC (59.3%), SGA (46.5%), NRI (16.3%), and INA (14.0%).

Conclusion:  The MI was the best single score to identify the patients who had malnutrition, including early stage, and may benefit from nutrition support.
Bacterial Community Composition in Central European Running Waters Examined by Temperature Gradient Gel Electrophoresis and Sequence Analysis of 16S rRNA Genes
Authors: Beier Sara , Witzel Karl-Paul , Marxsen Jürgen
Published: November 2007

The bacterial community composition in small streams and a river in central Germany was examined by temperature gradient gel electrophoresis (TGGE) with PCR products of 16S rRNA gene fragments and sequence analysis. Complex TGGE band patterns suggested high levels of diversity of bacterial species in all habitats of these environments. Cluster analyses demonstrated distinct differences among the communities in stream and spring water, sandy sediments, biofilms on stones, degrading leaves, and soil. The differences between stream water and sediment were more significant than those between sites within the same habitat along the stretch from the stream source to the mouth. TGGE data from an entire stream course suggest that, in the upper reach of the stream, a special suspended bacterial community is already established and changes only slightly downstream. The bacterial communities in water and sediment in an acidic headwater with a pH below 5 were highly similar to each other but deviated distinctly from the communities at the other sites. As ascertained by nucleotide sequence analysis, stream water communities were dominated byBetaproteobacteria(one-third of the total bacteria), whereas sediment communities were composed mainly ofBetaproteobacteriaand members of theFibrobacteres/Acidobacteriagroup (each accounting for about 25% of bacteria). Sequences obtained from bacteria from water samples indicated the presence of typical cosmopolitan freshwater organisms. TGGE bands shared between stream and soil samples, as well as sequences found in bacteria from stream samples that were related to those of soil bacteria, demonstrated the occurrence of some species in both stream and soil habitats. Changes in bacterial community composition were correlated with geographic distance along a stream, but in comparisons of different streams and rivers, community composition was correlated only with environmental conditions.
Genomic Markers for Differentiation of
Francisella tularensis
subsp.
tularensis
A.I and A.II Strains
Authors: Molins-Schneekloth Claudia R. , Belisle John T. , Petersen Jeannine M.
Published: November 2007

Tularemia is caused by two subspecies of
Francisella tularensis
,
F. tularensis
subsp.
tularensis
(type A) and
F. tularensis
subsp.
holarctica
(type B).
F. tularensis
subsp.
tularensis
is further subdivided into two genetically distinct populations (A.I and A.II) that differ with respect to geographical location, anatomical source of recovered isolates, and disease outcome. Using two human clinical isolates, suppression subtractive hybridization was performed to identify 13 genomic regions of difference between A.I and A.II strains. Two PCR assays, one to identify A.I and A.II as well as to discriminate between
F. tularensis
subsp.
holarctica
and
F. novicida
and another specific for A.I, were developed. This is the first report to identify and characterize conserved genomic differences between A.I and A.II.
Salmonella enterica
Burden in Harvest-Ready Cattle Populations from the Southern High Plains of the United States
Authors: Kunze David J. , Loneragan Guy H. , Platt Tammy M. , Miller Mark F. , Besser Thomas E. , Koohmaraie Mohammad , Stephens Tyler , Brashears Mindy M.
Published: November 2007

Our objectives were to quantify the
Salmonella enterica
burdens in harvest-ready cattle and to identify specific at-risk populations of cattle most likely to harbor multiply resistant
S. enterica
. Hide swabs were collected in abattoirs from three cohorts of cattle (feedlot origin cattle that had achieved desirable harvest characteristics and dairy- and beef-type cows harvested because of poor productivity). Feces were collected from two cohorts housed in feedlots (cattle that had achieved desirable harvest characteristics and animals identified for salvage recovery because of poor productivity). Facilities were visited on four occasions over a 12-month period.
Salmonella enterica
isolates were recovered, and organisms were quantified using standard microbiological methodologies. Susceptibility to antimicrobial drugs and serotype were determined for one
S. enterica
isolate per sample.
Salmonella enterica
was recovered from 55.6% of 1,681 samples. The prevalences on hides and in feces were 69.6% and 30.3%, respectively. The concentrations of
S. enterica
organisms averaged (as determined by the most probable number technique) 1.82 log
10
/100 cm
2
of hides and 0.75 log
10
/g of feces. None of the isolates recovered from cattle that had achieved desirable harvest characteristics were resistant to four or more drugs. For isolates recovered from animals with poor productivity characteristics, 6.5% were resistant to four or more drugs. Twenty-two serovars were identified, with the most common being
Salmonella enterica
serovar Anatum (25.5%),
Salmonella enterica
serovar Montevideo (22.2%), and
Salmonella enterica
serovar Cerro (12.5%). High-level resistance, i.e., resistance to four or more drugs, was clustered within a few relatively uncommon serovars. These results demonstrate that even though
S. enterica
isolates are readily recoverable from harvest-ready cattle, multiply resistant variants are rare and are associated with specific serovars in cattle harvested because of poor productivity characteristics.
Unique Structural Features of the Peptidoglycan ofMycobacterium leprae
Authors: Mahapatra Sebabrata , Crick Dean C. , McNeil Michael R. , Brennan Patrick J.
Published: November 2007

The peptidoglycan structure ofMycobacteriumspp. has been investigated primarily with the readily cultivableMycobacterium smegmatisandMycobacterium tuberculosisand has been shown to contain unusual features, including the occurrence of N-glycolylated, in addition to N-acetylated, muramic acid residues and direct cross-linkage betweenmeso-diaminopimelic acid residues. Based on results from earlier studies, peptidoglycan from in vivo-derived noncultivableMycobacterium lepraewas assumed to possess the basic structural features of peptidoglycans from other mycobacteria, other than the reported replacement ofl-alanine by glycine in the peptide side chains. In the present study, we have analyzed the structure ofM. lepraepeptidoglycan in detail by combined liquid chromatography and mass spectrometry. In contrast to earlier reports, and to the peptidoglycans inM. tuberculosisandM. smegmatis, the muramic acid residues ofM. lepraepeptidoglycan are exclusively N acetylated. The un-cross-linked peptide side chains ofM. lepraeconsist of tetra- and tripeptides, some of which contain additional glycine residues. Based on these findings and genome comparisons, it can be concluded that the massive genome decay inM. lepraedoes not markedly affect the peptidoglycan biosynthesis pathway, with the exception of the nonfunctionalnamHgene responsible forN-glycolylmuramic acid biosynthesis.
LuxS Affects Flagellar Phase Variation Independently of Quorum Sensing inSalmonella entericaSerovar Typhimurium
Authors: Karavolos M. H. , Bulmer D. M. , Winzer K. , Wilson M. , Mastroeni P. , Williams P. , Khan C. M. A.
Published: November 2007

LuxS catalyzes the synthesis of the quorum-sensing signaling molecule autoinducer 2. We show that inSalmonella entericaserovar Typhimurium, deletion of theluxSgene polarizes flagellar phase variation toward the more immunogenic phase 1 flagellin. This phenotype is complementable byluxSintransbut is independent of quorum-sensing signals.
Regulation of Motility by the ExpR/Sin Quorum-Sensing System in
Sinorhizobium meliloti
Authors: Hoang Hanh H. , Gurich Nataliya , González Juan E.
Published: November 2007

A successful symbiotic relationship between
Sinorhizobium meliloti
and its host
Medicago sativa
(alfalfa) depends on several signaling mechanisms, such as the biosynthesis of exopolysaccharides (EPS) by
S. meliloti
. Previous work in our laboratory has shown that a quorum-sensing mechanism controls the production of the symbiotically active EPS II. Recent microarray analysis of the whole-genome expression profile of
S. meliloti
reveals that the ExpR/Sin quorum-sensing system regulates additional physiological processes that include low-molecular-weight succinoglycan production, nitrogen utilization, metal transport, motility, and chemotaxis. Nearly half of the flagellar genes and their dependence on quorum sensing are prominently displayed in our microarray analyses. We extend those observations in this work and confirm the findings by real-time PCR expression analysis of selected genes, including the
flaF, flbT, flaC, cheY1
, and
flgB
genes, involved in motility and chemotaxis. These genes code for regulators of flagellum synthesis, the chemotactic response, or parts of the flagellar apparatus. Gene expression analyses and visualization of flagella by electron microscopy performed at different points in the growth phase support our proposed model in which quorum sensing downregulates motility in
S. meliloti
. We demonstrate that the ExpR/Sin quorum-sensing system controls motility gene expression through the VisN/VisR/Rem relay. We also show that the ExoS-dependent two-component system suppresses motility gene expression through VisN and Rem in parallel to quorum sensing. This study contributes to our understanding of the mechanisms that govern motility in
S. meliloti
.
A Naturally Occurring Gene Amplification Leading to Sulfonamide and Trimethoprim Resistance in
Streptococcus agalactiae
Authors: Brochet Mathieu , Couvé Elisabeth , Zouine Mohamed , Poyart Claire , Glaser Philippe
Published: November 2007

Gene amplifications have been detected as a transitory phenomenon in bacterial cultures. They are predicted to contribute to rapid adaptation by simultaneously increasing the expression of genes clustered on the chromosome. However, genome amplifications have rarely been described in natural isolates. Through DNA array analysis, we have identified two
Streptococcus agalactiae
strains carrying tandem genome amplifications: a fourfold amplification of 13.5 kb and a duplication of 92 kb. Both amplifications were located close to the terminus of replication and originated independently from any long repeated sequence. They probably arose in the human host and showed different stabilities, the 13.5-kb amplification being lost at a frequency of 0.003 per generation and the 92-kb tandem duplication at a frequency of 0.035 per generation. The 13.5-kb tandem amplification carried the five genes required for dihydrofolate biosynthesis and led to both trimethoprim (TMP) and sulfonamide (SU) resistance. Resistance to SU probably resulted from the increased synthesis of dihydropteroate synthase, the target of this antibiotic, whereas the amplification of the whole pathway was responsible for TMP resistance. This revealed a new mechanism of resistance to TMP involving an increased dihydrofolate biosynthesis. This is, to our knowledge, the first reported case of naturally occurring antibiotic resistance resulting from genome amplification in bacteria. The low stability of DNA segment amplifications suggests that their role in antibiotic resistance might have been underestimated.