bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantify single nucleotide polymorphism (SNP) ratio in pooled DNA based on normalized fluorescence real-time PCR
Authors: Yu Airong , Geng Haifeng , Zhou Xuerui 
Published: June 2006

Abstract

Background
Conventional real-time PCR to quantify the allele ratio in pooled DNA mainly depends on PCR amplification efficiency determination and Ct value, which is defined as the PCR cycle number at which the fluorescence emission exceeds the fixed threshold. Because of the nature of exponential calculation, slight errors are multiplied and the variations of the results seem too large. We have developed a new PCR data point analysis strategy for allele ratio quantification based on normalized fluorescence ratio.

Results
In our method, initial reaction background fluorescence was determined based upon fitting of raw fluorescence data to four-parametric sigmoid function. After that, each fluorescence data point was first subtracted by respective background fluorescence and then each subtracted fluorescence data point was divided by the specific background fluorescence to get normalized fluorescence. By relating the normalized fluorescence ratio to the premixed known allele ratio of two alleles in standard samples, standard linear regression equation was generated, from which unknown specimens allele ratios were extrapolated using the measured normalized fluorescence ratio. In this article, we have compared the results of the proposed method with those of baseline subtracted fluorescence ratio method and conventional Ct method.

Conclusion
Results demonstrated that the proposed method could improve the reliability, precision, and repeatability for quantifying allele ratios. At the same time, it has the potential of fully automatic allelic ratio quantification.
Genome-wide transcriptional analysis of temperature shift in L. interrogans serovar lai strain 56601
Authors: Qin Jin-Hong , Sheng Yue-Ying , Zhang Zhi-Ming , Shi Yao-Zhou , He Ping , Hu Bao-Yu , Yang Yang , Liu Shi-Gui , Zhao Guo-Ping , Guo Xiao-Kui 
Published: June 2006

Abstract

Background

Leptospira interrogans is an important mammalian pathogen. Transmission from an environmental source requires adaptation to a range of new environmental conditions in the organs and tissues of the infected host. Several studies have shown that a shift in culture temperature from 28°C to 37°C, similar to that encountered during infection of a host from an environmental source, is associated with differential synthesis of several proteins of the outer membrane, periplasm and cytoplasm. The whole genome of the Leptospira interrogans serogroup Icterohaemorrhagiae serovar lai type strain #56601 was sequenced in 2003 and microarrays were constructed to compare differential transcription of the whole genome at 37°C and 28°C.

Results
DNA microarray analyses were used to investigate the influence of temperature on global gene expression in L. interrogans grown to mid-exponential phase at 28°C and 37°C. Expression of 106 genes differed significantly at the two temperatures. The differentially expressed genes belonged to nine functional categories: Cell wall/membrane biogenesis genes, hemolysin genes, heat shock proteins genes, intracellular trafficking and secretion genes, two-component system and transcriptional regulator genes, information storage and processing genes, chemotaxis and flagellar genes, metabolism genes and genes with no known homologue. Real-time reverse transcription-PCR assays confirmed the microarray data.

Conclusion
Microarray analyses demonstrated that L. interrogans responds globally to temperature alteration. The data delineate the spectrum of temperature-regulated gene expression in an important human pathogen and provide many new insights into its pathogenesis.
Soluble egg antigen of Schistosoma Haematobiuminduces HCV replication in PBMC from patients with chronic HCV infection
Authors: El-Awady Mostafa K , Youssef Samar S , Omran Moataza H , Tabll Ashraf A , El Garf Wael T , Salem Ahmed M 
Published: June 2006

Abstract

Background
This study was conducted to examine, in vitro , the effect of soluble egg antigen (SEA) of
S. haematobium
on intracellular HCV RNA load in peripheral mononuclear cells (PBMC) as well as on cell proliferation in patients with chronic HCV infection.

Methods
PBMC from 26 patients with chronic HCV infection were cultured for 72 hours in presence and absence of 50 μg SEA/ml medium. Intracellular HCV RNA quantification of plus and minus strands was assessed before and after stimulation. PBMC from five healthy subjects were cultured for 7 days, flow cytometric analysis of DNA content was used to assess the mitogenic effect of SEA on PBMC proliferation compared to phytoheamaglutinine (PHA).

Results
Quantification of the intracellular viral load showed increased copy number/cell of both or either viral strands after induction with SEA in 18 of 26 patients (69.2%) thus indicating stimulation of viral replication. Flow cytometric analysis showed that mean ± S.D. of percent values of cell proliferation was induced from 3.2 ± 1.5% in un-stimulated cells to 16.7 ± 2.5 % and 16.84 ± 1.7 % in cells stimulated with PHA and SEA respectively.

Conclusion
the present study supports earlier reports on SEA proliferative activity on PBMC and provides a strong evidence that the higher morbidity observed in patients co-infected with schistosomiasis and HCV is related, at least in part, to direct stimulation of viral replication by SEA.
Is the NEI-VFQ-25 a useful tool in identifying visual impairment in an elderly population?
Authors: Owen Christopher G , Rudnicka Alicja R , Smeeth Liam , Evans Jennifer R , Wormald Richard PL , Fletcher Astrid E 
Published: June 2006

Abstract

Background
The use of self-report questionnaires to substitute for visual acuity measurement has been limited. We examined the association between visual impairment and self reported visual function in a population sample of older people in the UK.

Methods
Cross sectional study of people aged more than 75 years who initially participated in a trial of health screening. The association between 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ) scores and visual impairment (defined as an acuity of less than 6/18 in the better eye) was examined using logistic regression.

Results
Visual acuity and NEI-VFQ scores were obtained from 1807 participants (aged 77 to 101 years, 36% male), from 20 general practices throughout the UK. After adjustment for age, gender, practice and NEI-VFQ sub-scale scores, those complaining of poor vision in general were 4.77 times (95% CI 3.03 to 7.53) more likely to be visually impaired compared to those who did not report difficulty. Self-reported limitations with social functioning and dependency on others due to poor vision were also associated with visual impairment (odds ratios, 2.52, 95% CI 1.55 to 4.11; 1.73, 95% CI 1.05 to 2.86 respectively). Those reporting difficulties with near vision and colour vision were more likely to be visually impaired (odds ratios, 2.32, 95% CI 1.30 to 4.15; 2.25, 95% CI 1.35 to 3.73 respectively). Other NEI-VFQ sub-scale scores were unrelated to measures of acuity. Similar but weaker odds ratios were found with reduced visual acuity (defined as less than 6/12 in the better eye). Although differences in NEI-VFQ scores were small, scores were strongly associated with visual acuity, binocular status, and difference in acuity between eyes.

Conclusion
NEI-VFQ questions regarding the quality of general vision, social functioning, visual dependency, near vision and colour vision are strongly and independently associated with an objective measure of visual impairment in an elderly population.
Structural inversion of gravity data using linear programming
Authors: van Zon Tim , Roy-Chowdhury Kabir 
Published: June 2006

Structural inversion of gravity data — deriving robust images of the subsurface by delineating lithotype boundaries using density anomalies — is an important goal in a range of exploration settings (e.g., ore bodies, salt flanks). Application of conventional inversion techniques in such cases, using [Formula: see text]-norms and regularization, produces smooth results and is thus suboptimal. We investigate an [Formula: see text]-norm-based approach which yields structural images without the need for explicit regularization. The density distribution of the subsurface is modeled with a uniform grid of cells. The density of each cell is inverted by minimizing the [Formula: see text]-norm of the data misfit using linear programming (LP) while satisfying a priori density constraints. The estimate of the noise level in a given data set is used to qualitatively determine an appropriate parameterization. The 2.5D and 3D synthetic tests adequately reconstruct the structure of the test models. The quality of the inversion depends upon a good prior estimation of the minimum depth of the anomalous body. A comparison of our results with one using truncated singular value decomposition (TSVD) on a noisy synthetic data set favors the LP-based method. There are two advantages in using LP for structural inversion of gravity data. First, it offers a natural way to incorporate a priori information regarding the model parameters. Second, it produces subsurface images with sharp boundaries (structure).
MMT forward modeling for a layered earth with arbitrary anisotropy
Authors: Yin Changchun 
Published: June 2006

The standard model of a layered isotropic earth is a good approximation to geophysical reality in geoelectromagnetic mapping. In regions with distinct dipping stratification, however, it is difficult to model these fine structures because of large storage and time requirements. In this case, we may approximately replace the isotropic conductors with a preferential electrical direction by macro-scale anisotropy. The marine-magnetotelluric (MMT) forward problem is formulated for a layered earth with arbitrary anisotropy. For a given layer beneath the ocean, the two horizontal components of the electric field are projected onto the principal anisotropic directions and continued from layer to layer using continuity conditions. The formulation is used to derive the impedance tensor and apparent resistivities for a uniform anisotropic half-space, which clearly distinguish the effect of electrical anisotropy on MMT responses. The principal anisotropic orientations are clearly identified in the polar plots, which show the azimuthal variation of the apparent resistivity. The resolvability analysis of a resistive intermediate layer indicates that the depth of exploration for the MMT method depends strongly on the anomaly threshold associated with system sensitivity and environmental noise level but less on the resistivity contrast between the target and surrounding media. For an anisotropic target, to obtain a larger depth of exploration the electric field should be measured in the direction of higher target-host resistivity contrast. The simulation of reservoir characterization using marine MT shows that the current MMT technique cannot be an effective tool yet for direct offshore reservoir characterization, but it can be a good complementary tool for controlled-source electromagnetic (EM) technologies emerging for offshore hydrocarbon exploration.
Intraovarian Tumor Necrosis Factor-Related Weak Inducer of Apoptosis/Fibroblast Growth Factor-Inducible-14 Ligand-Receptor System Limits Ovarian Preovulatory Follicles from Excessive Luteinization
Authors: De Ananya , Park Jae-Il , Kawamura Kazuhiro , Chen Ruby , Klein Cynthia , Rauch Rami , Mulders Sabine M. , Sollewijn Gelpke Maarten D. , Hsueh Aaron J. W. 
Published: June 2006

Abstract
In addition to gonadotropins, many ovarian paracrine factors are crucial for optimal follicle rupture, oocyte maturation, and luteinization. Based on DNA microarray analyses, we found that transcripts for the fibroblast growth factor-inducible-14 (Fn14) receptor are increased after LH/human chorionic gonadotropin (hCG) treatment of gonadotropin-primed immature mice or rats. Fn14 is the cognate receptor for TNF-related weak inducer of apoptosis (TWEAK), a TNF superfamily member. TWEAK transcripts also were detected in the ovary; however, their levels were not regulated by gonadotropins. In situ hybridization analyses indicated that the Fn14 receptor is expressed in the granulosa and cumulus cells of preovulatory follicles and, to a lesser extent, in theca cells. In contrast, in situ hybridization analyses revealed that TWEAK is primarily expressed in theca cells. In cultured granulosa cells pretreated with hCG to induce Fn14 receptor expression, treatment with TWEAK suppressed progesterone synthesis without accompanying changes in cAMP production. Furthermore, intrabursal injection of TWEAK suppressed ovarian progesterone content in gonadotropin-primed rats. In contrast, preovulatory follicles cultured in the presence of the Fn14 decoy, a recombinant protein containing the ligand-binding domain of Fn14, led to increases in progesterone production, presumably by antagonizing the actions of endogenous TWEAK. Likewise, ip injection of the Fn14 decoy enhanced serum progesterone levels with accompanying increases in transcript levels for several key steroidogenic enzymes. The present findings demonstrate a suppressive role of the TWEAK/Fn14 signaling system in the ovary. Following gonadotropin induction of ovulation, Fn14 is induced and could protect preovulatory follicles from excessive luteinization.
The Human Growth Hormone Gene Contains a Silencer Embedded within an Alu Repeat in the 3′-Flanking Region
Authors: Trujillo Miguel A. , Sakagashira Michiko , Eberhardt Norman L. 
Published: June 2006

AbstractAlu family sequences are middle repetitive short interspersed elements (SINEs) dispersed throughout vertebrate genomes that can modulate gene transcription. The human (h) GH locus contains 44 complete and four partial Alu elements. An Sx Alu repeat lies in close proximity to the hGH-1 and hGH-2 genes in the 3′-flanking region. Deletion of the Sx Alu repeat in reporter constructs containing hGH-1 3′-flanking sequences increased reporter activity in transfected pituitary GC cells, suggesting this region contained a repressor element. Analysis of multiple deletion fragments from the 3′-flanking region of the hGH-1 gene revealed a strong orientation- and position-independent silencing activity mapping between nucleotides 2158 and 2572 encompassing the Sx Alu repeat. Refined mapping revealed that the silencer was a complex element comprising four discrete entities, including a core repressor domain (CRD), an antisilencer domain (ASE) that contains elements mediating the orientation-independent silencer activity, and two domains flanking the CRD/ASE that modulate silencer activity in a CRD-dependent manner. The upstream modulator domain is also required for orientation-independent silencer function. EMSA with DNA fragments representing all of the silencer domains yielded a complex pattern of DNA-protein interactions indicating that numerous GC cell nuclear proteins bind specifically to the CRD, ASE, and modulator domains. The silencer is GH promoter dependent and, in turn, its presence decreases the rate of promoter-associated histone acetylation resulting in a significant decrease of RNA polymerase II recruitment to the promoter. The silencer may provide for complex regulatory control of hGH gene expression in pituitary cells.
One-Pot Coupling of Two Alkynes and One Alkene for Formation of Cyclohexene Derivatives via Zirconacyclopentadienes
Authors: Zhou Lishan , Xi Chanjuan , Wang Hui , Kong Fanzhi , Takahashi Tamotsu 
Published: June 2006

Abstract
One-pot synthesis of cyclohexene derivatives from two alkynes and one maleic acid derivative could be achieved. Two alkynes were treated with [Cp2ZrBu2] to give zirconacyclopentadienes. Addition of 2 equiv of H2O followed by the reaction with maleic anhydride at 100 °C in toluene for 12 h afforded the cyclohexene derivatives in high yields. The corresponding titanacyclopentadiene did not give the desired product under the same conditions. In the case of Hf, only 8% of the product was obtained. Dienylzirconocene, which could be prepared by the addition of one equiv of EtOH or t-BuOH to the zirconacyclopentadiene, also reacted with maleic anhydride to give the cyclohexene derivative in 82 and 62% yield, respectively.
Effects of Calcitonin and Parathyroid Hormone on Calcification of Primary Cultures of Chicken Growth Plate Chondrocytes
Authors: Ishikawa Yoshinori , Wu Licia N. Y. , Genge Brian R. , Mwale Fackson , Dr. Wuthier Roy E. 
Published: June 2006

Abstract
Few studies have been directed toward elucidating the action of calcitonin (CT) and parathyroid hormone (PTH) on growth plate chondrocytes, cells directly involved in longitudinal bone growth and provisional calcification. In this study, primary cultures of avian growth plate chondrocytes that calcify without the supplement of β-glycerophosphate were used to investigate the effects of synthetic human CT and 1–34 bovine PTH on (1) cell division and growth; (2) the deposition of Ca2+ and inorganic phosphate (Pi); (3) the activity of alkaline phosphatase (AP), an enzyme long associated with the mineralization process; (4) the levels of proteoglycans; and (5) the synthesis of collagens. Added continually to preconfluent cultures from day 6 until harvest, CT (1–30 nM) and PTH (0.1–1.0 nM) increased mineral deposition; the maximal increase was seen between days 18–21 at 10 nM CT (175–260%) and 0.5 nM PTH (∼170–280%), both p &lt; 0.001. CT had no significant effect on cellular protein, or AP-specific activity, whereas PTH increased cellular protein, DNA, proteoglycan, and collagen content of the cultures in a dosage-dependent manner. AP activity and levels of Type II and X collagens and fibronectin in the culture medium showed a biphasic response to PTH; maximal increases were seen at 0.5 nM between days 15–18. Longer exposure (days 21–27) to PTH at higher levels (5–10 nM) caused a marked decrease in AP activity but a lesser decrease in the collagens. These results indicate that CT and PTH can act directly on chondrocytes to stimulate mineralization, but that PTH specifically stimulated cell division and synthesis of cellular and extracellular proteins by growth plate chondrocytes. The implications of these findings with regard to Ca2+ homeostasis and bone formation are discussed.
Osteoblasts Express Types I and II Activin Receptors During Early Intramembranous and Endochondral Bone Formation
Authors: Shuto Toshihide , Sarkar Gobinda , Bronk James T. , Matsui Nobuzo , Bolander Mark E. 
Published: June 2006

Abstract
Increasing evidence suggests a potential role for activin in bone formation. However, the cognate receptors through which activins function with respect to skeletal tissues have not yet been identified. Identification and regulation of expression of these receptors are necessary prerequisites to understanding the role of activins in bone metabolism. We detected mRNAs for three activin receptors, type I (ActRI), type II (ActRII), and type IIB (ActRIIB), in multiple skeletal tissues in rat, including tibia and costochondral growth plate, and also in cultured osteoblasts. To gain information about the relationship between receptor expression and different skeletal cell functions, we evaluated expression of the three receptors in a semiquantitative manner during the early stages of fracture healing, a model for rapid bone formation. Relatively high levels of ActRI and ActRII expression were detected in the callus at 7, 10, and 14 days after fracture, times that correlate with the interval of rapid intramembranous bone formation and the initiation of endochondral bone formation. Expression of the ActRIIB in the fracture callus was strikingly lower than either ActRI or ActRII. Immunostaining of the fracture callus and the newborn rat femur with an anti-ActRII antibody localized the receptor to osteoblasts at regions of membranous and endochondral bone formation. No staining of osteoblasts in fracture callus or bone was seen with an anti-ActRIIB antibody. These results provide strong evidence of the identification of the principal receptors through which activins could function in the skeletal system and further shed light on activin's mechanism of action in bone formation.
Humor and shyness: The relation between humor styles and shyness
Authors: Hampes William P 
Published: June 2006

AbstractThe Shyness Scale and Humor Styles Questionnaire were given to 174 subjects (69 male, 105 female). There was a significant negative correlation between shyness and affiliative humor for the total group, which was explained by the inability of shy people to relax enough in social situations to use this kind of humor. There was a significant positive correlation between shyness and self-defeating humor for the total group, a result that was expected due in large part to the low self-esteem of shy people. For the total group correlations between shyness and self-enhancing humor and between shyness and aggressive humor were not significant. Some of the sex differences between shy males versus shy females on aggressive and self-defeating humor were discussed.
Dolus eventualis und die dritte Schuldform
Authors: Papageorgiou-Gonatas Stylianos 
Published: June 2006

Abstract
Die Abgrenzungsfrage zwischen bewusster Fahrlässigkeit und bedingtem Vorsatz gehört zu den schwierigsten und umstrittensten Fragen in der Strafrechtsdogmatik. Sie hat jetzt in Griechenland eine besondere Bedeutung erlangt aufgrund der gesetzlichen Lage über den Dolus eventualis, die sich von der deutschen Rechtslage unterscheidet. Ausgelöst durch die aktuelle griechische Rechtsprechung innerhalb der letzten fünf Jahre zeigen sich neue Tendenzen für die Strafrechtswissenschaft, die von den traditionellen Theorien abzuweichen scheinen.
Effects of Particle Size and Shear Rate on Melt Flow Properties During Capillary Extrusion of Glass Bead-Filled LDPE Composites
Authors: Liang J-Z 
Published: June 2006

Abstract
The melt flow properties of a low-density polyethylene (LDPE) filled with glass brads (GB) were measured at 150°C by means a capillary rheometer to identify the effects of the particle size and extrusion rate on the melt flow behavior in the present paper. The volume fraction of the glass beads was 8.4 %. The surface of the particles had been treated with a silane-coupling agent and the diameter range was from 4 μm to 180 μm. The results showed that the entry pressure drop was a component function of apparent shear rate and the melt shear flow approximately obeyed the power law. The melt shear viscosity decreased roughly linearly with an increase of the wall shear stress, and it varied slightly with an addition of the bead diameter under various shear stress levels. Namely, the influence of the bead size on the melt flow properties of the LDPE/GB composites was insignificant at lower concentration of the fine spheres. This might be attributed to the relatively weak interfacial adhesion between the particles and the matrix due to the smooth spherical surface of the beads.