bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of pentoxifylline on liver regeneration after portal vein ligation in rats
Authors: Kucuktulu Uzer , Alhan Etem , Tekelioglu Yavuz , Ozekin Aysel 
Published: January 2007

AbstractAim: To determine the effects of pentoxifylline, a methyl xanthine derivative on hepatic cell production of uninterferred lobe after portal vein branch ligation.Methods: Sixty‐six rats were randomly allocated into 9 groups with 8 rats in PVL groups and 6 rats in sham operation groups. The portal branches of the median and the lateral liver lobes, corresponding to approximately 70% of the liver voluma were ligated in the PVL groups. The control group received 0.9% NaCl solution. The rats in the treatment groups received pentoxypilline at the dose of 50 mg/kg/dy. After 1,2,4 days of portal vein ligation in both PVL and PVNL lobes the levels of adenine nucleotides were determined and flowcytometric analysis of cell cycles were performed.Results: On the first day of portal branch ligation energy charge was significantly lower, in pentoxifylline treated group comparing to pentoxfylline untreated group, both in PVL and PVNL lobes (P<0.05). Proliferative indexes were 0.38 and 0.29 in pentoxifylline treated and pentoxifylline untreated PVNL lobes respectively (P<0.05).Conclusion: Pentoxifylline treatment resulted in an increase of percentage of calls entering mitosis phase on the first day after PVL, somehow accelerating the regenaration process.
Internodal function in normal and regenerated mammalian axons
Authors: Moldovan M. , Krarup C. 
Published: January 2007

AbstractAim:  Following Wallerian degeneration, peripheral myelinated axons have the ability to regenerate and, given a proper pathway, establish functional connections with targets. In spite of this capacity, the clinical outcome of nerve regeneration remains unsatisfactory. Early studies have found that regenerated internodes remain persistently short though this abnormality did not seem to influence recovery in conduction. It remains unclear to which extent abnormalities in axonal function itself may contribute to the poor outcome of nerve regeneration.Methods:  We review experimental evidence indicating that internodes play an active role in axonal function.Results:  By investigating internodal contribution to axonal excitability we have found evidence that axonal function may be permanently compromised in regenerated nerves. Furthermore, we illustrate that internodal function is also abnormal in regenerated human nerves.Conclusion:  The data suggest that persistently shorter regenerated internodes lead to increased Na+/K+‐pump activity in response to increased Na+ entry during conduction. This may impair axonal function during prolonged repetitive activity and drain the energy reserves of the axons.
“He lives as a Master”: Seventeenth-Century Masculinity, Gendered Teaching, and Careers of New England Schoolmasters
Authors: Preston Jo Anne 
Published: January 2007

You that are men and thoughts of manhood know,Be Just now to the Man who made you so.Martyr'd by Scholars the stabbed Cassian dies,And falls to cursed Lads a Sacrafice.Not so my Cheever; Not by Scholars slain,But Praised and Lov'd, and wished to Life again.Cotton Mather, 1708In New England, as in the country as a whole, teaching began as a male occupation. The earliest schoolmasters taught in small settlements of religious dissenters who had migrated to the wilderness of New England in the seventeenth century. The gendered meaning of teaching accompanied the social practice of hiring male teachers. Puritan minister Cotton Mather, in his passionate elegy for seventeenth-century New England schoolmaster Ezekiel Cheever, attests to the settlers' belief in the manliness of teachers. To Mather and other English settlers, the very term schoolmaster denoted masculine qualities. In Mather's own words: “He lives as a Master, the Term, which has been for above three thousand years, assign'd to the Life of a Man.” For Mather, teachers were not only male but embodied a particular vision of the masculine as well. Mather's vision of the ideal teacher, as having a specific kind of masculinity, was not unique to him. Drawing on English and Puritan traditions, the early New England colonists embraced an image of the ideal teacher that incorporated masculine virtues.
Activities ofdl-α-Difluoromethylarginine and Polyamine Analogues againstCryptosporidium parvumInfection in a T-Cell Receptor Alpha-Deficient Mouse Model
Authors: Yarlett Nigel , Waters W. Ray , Harp James A. , Wannemuehler Michael J. , Morada Mary , Bellcastro Josephine , Upton Steve J. , Marton Laurence J. , Frydman Benjamin J. 
Published: January 2007

ABSTRACTThe in vivo effectiveness of a series of conformationally restricted polyamine analogues alone and selected members in combination withdl-α-difluoromethylarginine againstCryptosporidium parvuminfection in a T-cell receptor alpha-deficient mouse model was tested. Polyamine analogues were selected from the extended bis(ethyl)-sym-homospermidine or bis(ethyl)-spermine backbone havingcisortransdouble bonds at the center of the molecule. Thecisisomers were found to have significantly greater efficacy in both preventing and curing infection in a mouse model than thetranspolyamine analogues when tested in a T-cell receptor alpha-deficient mouse model. When tested in combination withdl-α-difluoromethylarginine, thecis-restricted analogues were found to be more effective in preventing oocyst shedding. This study demonstrates the potential of polyamine analogues as anticryptosporidial agents and highlights the presence of multiple points in polyamine synthesis by this parasite that are susceptible to inhibition resulting in growth inhibition.
Infection withToxoplasma gondiiBradyzoites Has a Diminished Impact on Host Transcript Levels Relative to Tachyzoite Infection
Authors: Fouts A. E. , Boothroyd J. C. 
Published: January 2007

ABSTRACTToxoplasma gondii, an intracellular pathogen, has the potential to infect nearly every warm-blooded animal but rarely causes morbidity. The ability for the parasite to convert to the bradyzoite stage and live inside slow-growing cysts that can go unnoticed by the host immune system allows for parasite persistence for the life of the infected host. This intracellular survival likely necessitates host cell modulation, and tachyzoites are known to modify a number of signaling cascades within the host to promote parasite survival. Little is known, however, about how bradyzoites manipulate their host cell. Microarrays were used to profile the host transcriptional changes caused by bradyzoite infection and compared to those of tachyzoite-infected and uninfected hosts cells 2 days postinfection in vitro. Infection resulted in chemokine, cytokine, extracellular matrix, and growth factor transcript level changes. A small group of genes were specifically induced by tachyzoite infection, including granulocyte-macrophage colony-stimulating factor, BCL2-related protein A1, and interleukin-24. Bradyzoite infection yielded only about half the changes seen with tachyzoite infection, and those changes that did occur were almost all of lower magnitude than those induced by tachyzoites. These results suggest that bradyzoites lead a more stealthy existence within the infected host cell.
An Increase in Epithelial Cell Apoptosis Is Associated with Chronic Intestinal Nematode Infection
Authors: Cliffe Laura J. , Potten Christopher S. , Booth Catherine E. , Grencis Richard K. 
Published: January 2007

ABSTRACTIt is well established that homeostasis of the intestinal epithelium becomes dysregulated during gastrointestinal helminth infection and is under immune control. An increase in both enterocyte proliferation and the subsequent generation of crypt hyperplasia are hallmarks of chronic infection withTrichuris muris, a large intestinal dwelling nematode. The effect of this parasitic infection on apoptosis induction in the large intestine and its regulation has been neglected. To address this, mice of resistant and susceptible phenotypes were infected with different doses ofT. muris, and the levels of epithelial cell apoptosis were determined. It is clear that apoptosis is induced during chronicT. murisinfection. This occurs mainly at the base of the cecal crypt, within the stem cell region. The level of apoptosis induced is independent of worm number, suggesting that it is not a consequence of worm-induced damage but rather a mechanism for controlling cell number within the crypt. Neutralization of both gamma interferon and tumor necrosis factor alpha caused a significant reduction in the levels of apoptosis, showing that proinflammatory cytokines generated in response to chronic infection play an important role in apoptosis induction in this system. It is proposed that the generation of proinflammatory cytokines during chronicT. murisinfection may play a positive role, by promoting intestinal epithelial cell apoptosis, to counter infection-induced epithelial hyperplasia.
Pertussis Toxin Targets Airway Macrophages To PromoteBordetella pertussisInfection of the Respiratory Tract
Authors: Carbonetti Nicholas H. , Artamonova Galina V. , Van Rooijen Nico , Ayala Victor I. 
Published: January 2007

ABSTRACTPertussis toxin (PT), a secreted virulence factor ofBordetella pertussis, ADP ribosylates mammalian Giproteins and plays an important early role in respiratory tract infection by this pathogen in a mouse intranasal infection model. To test the hypothesis that PT targets resident airway macrophages (AM) to promote this infection, we depleted AM by intranasal administration of liposome-encapsulated clodronate prior to bacterial inoculation. This treatment enhanced respiratory tract infection byB. pertussis, even though it also induced a rapid influx of neutrophils to the airways. Strikingly, AM depletion also enhanced infection by mutant strains deficient in PT production or activity to the same level as the wild-type infection, indicating that AM may be the primary target cells for PT in promoting infection. The enhancing effect of clodronate-liposome treatment on infection (i) was shown to be due to macrophage depletion rather than neutrophil influx; (ii) was observed for both tracheal infection and lung infection; (iii) was observed during the early and peak phases of the infection but was lost by day 14 postinoculation, during clearance of the infection; (iv) persisted for at least 1 week (prior to bacterial inoculation); and (v) was equivalent in magnitude to the effect of PT pretreatment and the effects were not additive, consistent with the idea that PT targets AM. We found that PT efficiently ADP ribosylated AM G proteins both in vitro and after intranasal administration of PT in mice and that the duration of G protein modification in vivo was equivalent to the duration of the enhancing effect of PT treatment on the bacterial infection. Collectively, these observations indicate that PT targets AM to promote early infection of the respiratory tract byB. pertussis.
Mouse Model of Oral Infection with Virulent Type A
Francisella tularensis
Authors: KuoLee R. , Zhao X. , Austin J. , Harris G. , Conlan J. W. , Chen W. 
Published: January 2007

ABSTRACT

Francisella tularensis
is a gram-negative facultative intracellular pathogen and the causative agent of tularemia. Little is known about the immunopathogenesis of oral infection with this pathogen. Here, for the first time, we examined the susceptibility of mice to intragastric inoculation with virulent type A
F. tularensis
and characterized the course of infection and the associated host responses. Both immunocompetent and immunodeficient mice were relatively susceptible to intragastric inoculation of type A
F. tularensis
with a 50% lethal dose (LD
50
) of 10
6
organisms, which was 100,000-fold higher than the LD
100
for intradermal or respiratory routes of infection. Mice deficient in gamma interferon or tumor necrosis factor receptors 1 and 2 were more susceptible than wild-type controls to oral infection with a high dose of the pathogen. After oral inoculation,
F. tularensis
appeared first in the mesenteric lymph nodes (MLN) and then rapidly spread to the livers and spleens, where the organism multiplied to high numbers and induced marked neutrophilic infiltration and severe tissue necrosis. Infected mice showed rapid increases in tissue cytokine mRNA expression, which peaked in the MLN at 2 days postinfection (dpi) and in the liver and spleen at 3 dpi. The levels of gamma interferon, interleukin-1β (IL-1β), IL-6, tumor necrosis factor alpha, macrophage inflammatory protein 1α, KC, interferon-inducible protein 10, and monocyte chemotactic protein 1 were elevated from day 2 postinoculation onward. Moreover, mice intradermally immunized with the live vaccine strain of
F. tularensis
showed little survival advantage over naive mice after oral challenge with type A
F. tularensis
. These results suggest that type A
F. tularensis
is an effective oral pathogen that can cause fatal systemic infection and could pose a public health concern, particularly to immunocompromised individuals, if ingested in contaminated water and food.
PhyloScan: identification of transcription factor binding sites using cross-species evidence
Authors: Carmack C Steven , McCue Lee Ann , Newberg Lee A , Lawrence Charles E 
Published: January 2007

Abstract

Background
When transcription factor binding sites are known for a particular transcription factor, it is possible to construct a motif model that can be used to scan sequences for additional sites. However, few statistically significant sites are revealed when a transcription factor binding site motif model is used to scan a genome-scale database.

Methods
We have developed a scanning algorithm, PhyloScan, which combines evidence from matching sites found in orthologous data from several related species with evidence from multiple sites within an intergenic region, to better detect regulons. The orthologous sequence data may be multiply aligned, unaligned, or a combination of aligned and unaligned. In aligned data, PhyloScan statistically accounts for the phylogenetic dependence of the species contributing data to the alignment and, in unaligned data, the evidence for sites is combined assuming phylogenetic independence of the species. The statistical significance of the gene predictions is calculated directly, without employing training sets.

Results
In a test of our methodology on synthetic data modeled on seven Enterobacteriales, four Vibrionales, and three Pasteurellales species, PhyloScan produces better sensitivity and specificity than MONKEY, an advanced scanning approach that also searches a genome for transcription factor binding sites using phylogenetic information. The application of the algorithm to real sequence data from seven Enterobacteriales species identifies novel Crp and PurR transcription factor binding sites, thus providing several new potential sites for these transcription factors. These sites enable targeted experimental validation and thus further delineation of the Crp and PurR regulons in E. coli.

Conclusion
Better sensitivity and specificity can be achieved through a combination of (1) using mixed alignable and non-alignable sequence data and (2) combining evidence from multiple sites within an intergenic region.
Vitamin D pathway gene polymorphisms, diet, and risk of postmenopausal breast cancer: a nested case-control study
Authors: McCullough Marjorie L , Stevens Victoria L , Diver William R , Feigelson Heather S , Rodriguez Carmen , Bostick Robin M , Thun Michael J , Calle Eugenia E 
Published: January 2007

Abstract
Introduction
Vitamin D receptor (VDR) polymorphisms have been inconsistently associated with breast cancer risk. Whether risk is influenced by polymorphisms in other vitamin D metabolism genes and whether calcium or vitamin D intake modifies risk by genotype have not been evaluated.

Methods
We conducted a nested case-control study within the Cancer Prevention Study II Nutrition Cohort of associations between breast cancer and four VDR single-nucleotide polymorphisms (SNPs), Bsm1,Apa1,Taq1, and Fok1, a poly(A) microsatellite, and associated haplotypes (baTL and BAtS). We also examined one SNP in the 24-hydroxylase gene (CYP24A1) and two in the vitamin D-binding protein (group-specific component [GC]) gene. Participants completed a questionnaire on diet and medical history at baseline in 1992. This study includes 500 postmenopausal breast cancer cases and 500 controls matched by age, race/ethnicity, and date of blood collection.

Results
Incident breast cancer was not associated with any genotype examined. However, women with the Bsm1 bb SNP who consumed greater than the median intake of total calcium (≥902 mg/day) had lower odds of breast cancer compared to women with the Bb or BB genotype and less than the median calcium intake (odds ratio 0.61, 95% confidence interval 0.38 to 0.96; pinteraction = 0.01). Similar interactions were observed for Taq1 (T allele) and the poly(A) (LL) repeat.

Conclusion
We found no overall association between selected vitamin D pathway genes and postmenopausal breast cancer risk. However, certain VDR gene polymorphisms were associated with lower risk in women consuming high levels of calcium, suggesting that dietary factors may modify associations by VDR genotype.
Post-earthquake behaviour of footings employing densification to mitigate liquefaction
Authors: Coelho P. A. L. F. , Haigh S. K. , Gopal Madabhushi S. P. , O'brien T. S. 
Published: January 2007

In situ densification is a popular technique to protect shallow foundations from the effects of earthquakeinduced liquefaction, current design being based on semiempirical rules. Poor understanding of the mechanisms governing the performance of soil—structure systems during and after earthquakes inhibits the use of narrow densified zones, which could contribute to optimise the use of densification if the increase in post-earthquake settlement is restrained. Therefore this paper investigates the long-term behaviour of a footing built on densified ground and surrounded by liquefiable ground, centrifuge experiments being used to identify the mechanisms occurring in the ground during and after a seismic simulation. The differential excess pore pressure generated in the ground during the shaking and the processes of vertical stress concentration and subsequent redistribution observed under the footing dominate the system behaviour. The results enlighten the complex mechanisms determining the post-earthquake settlement when densification is carried out to mitigate liquefaction effects. The improvement in performance resulting from widening the zone of densification is rationally explained which encourages the development of new design concepts that may enhance the future use of densification as a liquefaction resistance measure. La densification in situ est une technique courante pour protéger les fondations peu profondes contre les effets de liquéfaction due aux tremblements de terre, les structures actuelles étant basées sur des lois semi-empiriques. La compréhension limitée des mécanismes gouvernant les performances des systèmes sol-structure pendant et après les tremblements de terre empêche l'utilisation de zones densifiées étroites, qui pourrait contribuer à optimiser l'exploitation de la densification si l'augmentation en tassement après tremblement de terre est restreinte. Cet article étudie pour cette raison le comportement à long terme d'un bâti de semelle sur un sol densifié et entouré de sol liquéfiable. Des expériences en centrifugeuse sont réalisées pour déterminer les mécanismes mis en jeu dans le sol pendant et après une simulation de séisme. L'excédent de pression interstitielle différentiel généré dans le sol pendant les vibrations et les processus de concentration de contrainte verticale et de redistribution subséquente observés sous la semelle dominent le comportement du système. Ces résultats soulignent la complexité des mécanismes qui régissent le tassement du sol après un tremblement de terre lorsque la densification est utilisée pour atténuer les effets de liquéfaction. L'amélioration des performances résultant de l'élargissement de la zone de densification s'explique de manière rationnelle, ce qui encourage le développement de nouveaux concepts de structures qui peuvent étendre à l'avenir l'utilisation de la densification comme moyen de résistance à la liquéfaction.
Genetic Analysis of Triticum compactum L. var. amplissifolium Zhuk. Producing Curved Grain
Authors: Tomar S. M. S. , Menon M. K. , Vinod  , Sivasamy M. , Singh B. 
Published: January 2007

ABSTRACTThe hexaploid wheat species Triticum aestivum L. ssp compactum var. amplissifolium Zhuk. produces small plump but curved or boat shaped kernels with low thousand kernel weight. The grain number per unit spike length is high. The trait curved grain seems to be rare. The genetic analysis in F2 (T. aestivum cv. NI5439 × T. amplissifolium), BC1 (F1 × NI5439) and F3 generations revealed that the curved grain is governed by a single dominant gene. The gene symbol Cvg is proposed for this trait. The curved nature of the grain could serve as a useful morphological marker. The characters short spike and kernel color are also controlled by a single but independent gene. The number of grains per unit spike length and 1000 kernel weight are presumably governed by more than one gene and both the traits showed some association with the character short spike. The linkage analysis indicated that the character curved grain is linked with short spike length and the distance between these characters is 7.63 Kosambi unit.
Identification of Field Tolerance to Bean Pod Mottle and Soybean Mosaic Viruses in Soybean
Authors: Hill J. H. , Koval N. C. , Gaska J. M. , Grau C. R. 
Published: January 2007

ABSTRACTDevelopment of a method to identify field tolerance to bean pod mottle and soybean mosaic viruses (BPMV and SMV) in soybean [Glycine max (L.) Merr.] allowed evaluation of 33 soybean accessions for field response to BPMV and SMV. Based on measurement of parameters that included relative level of virus antigen in seed and mottling of soybean seed coats, three accessions showed tolerance to SMV and BPMV (PI 561353, M90‐18411, PI 507353), eight were tolerant to SMV (MN 1301, M92‐160047, M91‐113037, PI 423826A, A99‐216031, NE 3001, U96‐2408, Colfax), and four were tolerant to BPMV (PI 184042, M93‐326056, M95‐255017, Spansoy 201). Treatment of seed with the insecticide imidacloprid (1‐[(6‐chloro‐3‐pyridinyl)methyl]‐N‐nitro‐2‐imidazolidinimine) did not effect disease control. The relative level of virus antigen in seed harvested from experimental plots was shown to correlate significantly with virus incidence in plots. The data suggest that quantitative assay of virus seed antigen may provide a useful estimate of relative virus incidence in test plots and aid identification of field tolerance to seed‐borne viruses.