bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conserved Symbiotic Plasmid DNA Sequences in the Multireplicon Pangenomic Structure of
Rhizobium etli
Authors: González Víctor , Acosta José L. , Santamaría Rosa I. , Bustos Patricia , Fernández José L. , Hernández González Ismael L. , Díaz Rafael , Flores Margarita , Palacios Rafael , Mora Jaime , Dávila Guillermo 
Published: January 2010

ABSTRACT

Strains of the same bacterial species often show considerable genomic variation. To examine the extent of such variation in
Rhizobium etli
, the complete genome sequence of
R. etli
CIAT652 and the partial genomic sequences of six additional
R. etli
strains having different geographical origins were determined. The sequences were compared with each other and with the previously reported genome sequence of
R. etli
CFN42. DNA sequences common to all strains constituted the greater part of these genomes and were localized in both the chromosome and large plasmids. About 700 to 1,000 kb of DNA that did not match sequences of the complete genomes of strains CIAT652 and CFN42 was unique to each
R. etli
strain. These sequences were distributed throughout the chromosome as individual genes or chromosomal islands and in plasmids, and they encoded accessory functions, such as transport of sugars and amino acids, or secondary metabolism; they also included mobile elements and hypothetical genes. Sequences corresponding to symbiotic plasmids showed high levels of nucleotide identity (about 98 to 99%), whereas chromosomal sequences and the sequences with matches to other plasmids showed lower levels of identity (on average, about 90 to 95%). We concluded that
R. etli
has a pangenomic structure with a core genome composed of both chromosomal and plasmid sequences, including a highly conserved symbiotic plasmid, despite the overall genomic divergence.
Intranasal Vaccinations with the
trans
-Sialidase Antigen plus CpG Adjuvant Induce Mucosal Immunity Protective against Conjunctival
Trypanosoma cruzi
Challenges
Authors: Giddings O. K. , Eickhoff C. S. , Sullivan N. L. , Hoft D. F. 
Published: January 2010

ABSTRACT

Trypanosoma cruzi
is an intracellular protozoan parasite capable of infecting through mucosal surfaces. Our laboratory has previously elucidated the anatomical routes of infection after both conjunctival and gastric challenge in mice. We have shown that chronically infected mice develop strong immune responses capable of protecting against subsequent rechallenge with virulent parasites through gastric, conjunctival, and systemic routes of infection. We have also shown that intranasal immunizations with the unique
T. cruzi trans
-sialidase (TS) antigen protect against gastric and systemic
T. cruzi
challenge. In the current work we have investigated the ability of purified TS adjuvanted with CpG-containing oligonucleotides to induce immunity against conjunctival
T. cruzi
challenge. We confirm that intranasal vaccinations with TS plus CpG induce TS-specific T-cell and secretory IgA responses. TS-specific secretory IgA was detectable in the tears of vaccinated mice, the initial body fluid that contacts the parasite during infectious conjunctival exposures. We further show that intranasal vaccinations with TS plus CpG protect against conjunctival
T. cruzi
challenge, limiting local parasite replication at the site of mucosal invasion and systemic parasite dissemination. We also provide the first direct evidence that mucosal antibodies induced by intranasal TS vaccination can inhibit parasite invasion.
Pore Formation Triggered byLegionellaspp. Is an Nlrc4 Inflammasome-Dependent Host Cell Response That Precedes Pyroptosis
Authors: Silveira Tatiana N. , Zamboni Dario S. 
Published: January 2010

ABSTRACTLegionella pneumophila, the etiological agent of Legionnaires disease, is known to trigger pore formation in bone marrow-derived macrophages (BMMs) by mechanisms dependent on the type IVB secretion system known as Dot/Icm. Here, we used several mutants ofL. pneumophilain combination with knockout mice to assess the host and bacterial factors involved in pore formation in BMMs. We found that regardless of Dot/Icm activity, pore formation does not occur in BMMs deficient in caspase-1 and Nlrc4/Ipaf. Pore formation was temporally associated with interleukin-1β secretion and preceded host cell lysis and pyroptosis. Pore-forming ability was dependent on bacterial Dot/Icm but independent of several effector proteins, multiplication, andde novoprotein synthesis. Flagellin, which is known to trigger the Nlrc4 inflammasome, was required for pore formation asflaAmutant bacteria failed to induce cell permeabilization. Accordingly, transfection of purified flagellin was sufficient to trigger pore formation independent of infection. By using 11 differentLegionellaspecies, we found robust pore formation in response toL. micdadei,L. bozemanii,L. gratiana,L. jordanis, andL. rubrilucens, and this trait correlated with flagellin expression by these species. Together, the results suggest that pore formation is neitherL. pneumophilaspecific nor the result of membrane damage induced by Dot/Icm activity; instead, it is a highly coordinated host cell response dependent on host Nlrc4 and caspase-1 and on bacterial flagellin and type IV secretion system.
Suppression ofPlasmodium cynomolgiin Rhesus Macaques by Coinfection withBabesia microti
Authors: van Duivenvoorde Leonie M. , Voorberg-van der Wel Annemarie , van der Werff Nicole M. , Braskamp Gerco , Remarque Edmond J. , Kondova Ivanela , Kocken Clemens H. M. , Thomas Alan W. 
Published: January 2010

ABSTRACTBothPlasmodiumandBabesiaspecies are intraerythrocytic protozoans that infect a wide range of hosts, including humans, and they elicit similar inflammatory responses and clinical manifestations that differ markedly in severity. We recently reported that a rhesus macaque that was chronically infected withBabesia microtiwas able to control infection withPlasmodium cynomolgi(a parasite of macaques with characteristics very similar to those ofPlasmodium vivax) better than naïve monkeys. To confirm this and to investigate the underlying immunopathology, six naïve rhesus monkeys were infected withB. microti. After 24 days, four of these monkeys and four naïve rhesus monkeys were challenged withP. cynomolgiblood-stage parasites.B. microtipersisted at low levels in all monkeys, and the clinical parameters were comparable to those of noninfected controls. There was a significant decrease inP. cynomolgiparasitemia in animals coinfected withB. microticompared to the parasitemia in animals infected withP. cynomolgialone. This decrease inP. cynomolgiparasitemia correlated with increases in the levels of proinflammatory monocytes at the time ofP. cynomolgiinfection and with higher C-reactive protein (CRP) serum levels 1 week after malaria infection. Therefore, we conclude that ongoing infection withB. microtiparasites leads to suppression of malaria infection.
The Ferrichrome Uptake Pathway inPseudomonas aeruginosaInvolves an Iron Release Mechanism with Acylation of the Siderophore and Recycling of the Modified Desferrichrome
Authors: Hannauer Mélissa , Barda Yaniv , Mislin Gaëtan L. A. , Shanzer Abraham , Schalk Isabelle J. 
Published: January 2010

ABSTRACTThe uptake of iron intoPseudomonas aeruginosais mediated by two major siderophores produced by the bacterium, pyoverdine and pyochelin. The bacterium is also able of utilize several heterologous siderophores of bacterial or fungal origin. In this work, we have investigated the iron uptake inP. aeruginosaPAO1 by the heterologous ferrichrome siderophore.55Fe uptake assays showed that ferrichrome is transported across the outer membrane primarily (80%) by the FiuA receptor and to a lesser extent (20%) by a secondary transporter. Moreover, we demonstrate that like in the uptake of ferripyoverdine and ferripyochelin, the energy required for both pathways of ferrichrome uptake is provided by the inner membrane protein TonB1. Desferrichrome-55Fe uptake inP. aeruginosawas also dependent on the expression of the permease FiuB, suggesting that this protein is the inner membrane transporter of the ferrisiderophore. A biomimetic fluorescent analogue of ferrichrome, RL1194, was usedin vivoto monitor the kinetics of iron release from ferrichrome inP. aeruginosain real time. This dissociation involves acylation of ferrichrome and its biomimetic analogue RL1194 and recycling of both modified siderophores into the extracellular medium. FiuC, anN-acetyltransferase, is certainly involved in this mechanism of iron release, since its mutation abolished desferrichrome-55Fe uptake. The acetylated derivative reacts with iron in the extracellular medium and is able to be taken up again by the cells. All these observations are discussed in light of the current knowledge concerning ferrichrome uptake inP. aeruginosaand inEscherichia coli.
Magnetic resonance spectroscopy of extra-terrestrial methyl radical
Authors: Weil J. A. , Howarth D. F. 
Published: January 2010

The particular molecule discussed in some detail herein is the methyl radical, CH3, with emphasis on its potential extraterrestrial appearance. In earlier papers, including group-theoretical analysis, it was shown that the isotropic EPR spectra of free radical (S = 1/2) species XLn, where the n equivalent nuclei also have spin 1/2, have a more complicated form than disclosed by the usual (first-order) oversimplified analysis. In the present work, we focus on the magnetic resonance of such systems at or near zero external magnetic field, and on the spectra obtained both by perpendicular [Formula: see text] and parallel-field [Formula: see text] excitation. This work summarizes what is known about the spin-flip transitions of CH3, and predicts what likely will be observed (0–200 MHz, under various field and scan conditions), for the future use by astrophysicists.
Some electron probe X-ray microanalysis (EPMA)- and (BPES)-related physical investigations on ZnSSe thin-films growth composition-related kinetics
Authors: Fridjine S. , Boubaker K. , Amlouk M. 
Published: January 2010

In this study, ZnSSe epilayers were grown on (111) ZnS sprayed thin films. The spectral analysis was carried out in the region from 400 to 1800 nm. Analyses of the transmittance and (or) reflectance spectra indicate a decrease of the band gap energy value Eg with selenization. As the selenization process changes the structure and property of prepared materials and therefore has a direct effect on their physical properties, one of the concerns of this paper is to investigate the depth-dependent composition changes as guides to monitoring the selenization kinetics. Photothermal, atomic force microscopy (AFM), and X-ray diffraction (XRD) investigations have also been carried out.
An atom chip for the manipulation of ultracold atoms
Authors: Cherry O. , Carter J. D. , Martin J. D.D. 
Published: January 2010

We have fabricated an atom chip that magnetically traps laser cooled 87Rb by generating high magnetic-field gradients using micrometre scale current-carrying wires. The wires are fabricated on a Si wafer (with a 40 nm SiO2 layer) using 1.2 μm thick Au and a 20 nm thick adhesion layer, and are patterned with lift-off photolithography. We characterize the number and temperature of the cold atoms trapped by the chip.
Research challenges for digital archives of 3D cultural heritage models
Authors: Koller David , Frischer Bernard , Humphreys Greg 
Published: January 2010

The increasing creation of 3D cultural heritage models has resulted in a need for the establishment of centralized digital archives. We advocate open repositories of scientifically authenticated 3D models based on the example of traditional scholarly journals, with standard mechanisms for preservation, peer review, publication, updating, and dissemination of the 3D models. However, fully realizing this vision will require addressing a number of related research challenges.
In this article, we first give a brief background of the virtual heritage discipline, and characterize the need for centralized 3D archives, including a preliminary needs assessment survey of virtual heritage practitioners. Then we describe several existing 3D cultural heritage repositories, and enumerate a number of technical research challenges that should be addressed to realize an ideal archive. These challenges include digital rights management for the 3D models, clear depiction of uncertainty in 3D reconstructions, version control for 3D models, effective metadata structures, long-term preservation, interoperability, and 3D searching. Other concerns are provision for the application of computational analysis tools, and the organizational structure of a peer-reviewed 3D model archive.
Pomegranate Ellagitannin–Derived Compounds Exhibit Antiproliferative and Antiaromatase Activity in Breast Cancer Cells In vitro
Authors: Adams Lynn S. , Zhang Yanjun , Seeram Navindra P. , Heber David , Chen Shiuan 
Published: January 2010

Abstract
Estrogen stimulates the proliferation of breast cancer cells and the growth of estrogen-responsive tumors. The aromatase enzyme, which converts androgen to estrogen, plays a key role in breast carcinogenesis. The pomegranate fruit, a rich source of ellagitannins (ET), has attracted recent attention due to its anticancer and antiatherosclerotic properties. On consumption, pomegranate ETs hydrolyze, releasing ellagic acid, which is then converted to 3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-one (“urolithin”) derivatives by gut microflora. The purpose of this study was to investigate the antiaromatase activity and inhibition of testosterone-induced breast cancer cell proliferation by ET-derived compounds isolated from pomegranates. A panel of 10 ET-derived compounds including ellagic acid, gallagic acid, and urolithins A and B (and their acetylated, methylated, and sulfated analogues prepared in our laboratory) were examined for their ability to inhibit aromatase activity and testosterone-induced breast cancer cell proliferation. Using a microsomal aromatase assay, we screened the panel of ET-derived compounds and identified six with antiaromatase activity. Among these, urolithin B (UB) was shown to most effectively inhibit aromatase activity in a live cell assay. Kinetic analysis of UB showed mixed inhibition, suggesting more than one inhibitory mechanism. Proliferation assays also determined that UB significantly inhibited testosterone-induced MCF-7aro cell proliferation. The remaining test compounds also exhibited antiproliferative activity, but to a lesser degree than UB. These studies suggest that pomegranate ET–derived compounds have potential for the prevention of estrogen-responsive breast cancers. Cancer Prev Res; 3(1); 108–13
Atorvastatin and Celecoxib in Combination Inhibits the Progression of Androgen-Dependent LNCaP Xenograft Prostate Tumors to Androgen Independence
Authors: Zheng Xi , Cui Xiao-Xing , Gao Zhi , Zhao Yang , Lin Yong , Shih Weichung Joe , Huang Mou-Tuan , Liu Yue , Rabson Arnold , Reddy Bandaru , Yang Chung S. , Conney Allan H. 
Published: January 2010

Abstract
Epidemiology studies suggest that statins and nonsteroidal anti-inflammatory drugs reduce the risk of prostate cancer. In the present study, LNCaP cells were cultured in regular medium containing fetal bovine serum or in medium supplemented with charcoal-stripped fetal bovine serum to mimic androgen deprivation treatment. We found that atorvastatin (Lipitor) or celecoxib (Celebrex) treatment of LNCaP cells cultured in regular or androgen-depleted medium inhibited growth and stimulated apoptosis. A combination of atorvastatin and celecoxib was more effective than either agent alone. In animal studies, severe combined immunodeficient mice were injected s.c. with LNCaP cells in Matrigel. After 4 to 6 weeks, mice with LNCaP tumors (about 0.6 cm wide and 0.6 cm long) were surgically castrated and received daily i.p. injections of vehicle, atorvastatin (10 μg/g body weight/d), celecoxib (10 μg/g/d), or a combination of atorvastatin (5 μg/g/d) and celecoxib (5 μg/g/d) for 42 days. In all groups, the androgen-dependent LNCaP tumors regressed initially in response to castration, but the tumors eventually progressed to androgen independence and started to grow. Treatment of the mice with atorvastatin or celecoxib alone suppressed the regrowth of LNCaP tumors after castration. A combination of low doses of atorvastatin and celecoxib had a more potent effect in inhibiting the growth and progression of LNCaP tumors to androgen independence than a higher dose of either agent alone. Our results indicate that administration of a combination of atorvastatin and celecoxib may be an effective strategy for the prevention of prostate cancer progression from androgen dependence to androgen independence. Cancer Prev Res; 3(1); 114–24
A Randomized, Double-Blind, Placebo-Controlled Phase 3 Skin Cancer Prevention Study of α-Difluoromethylornithine in Subjects with Previous History of Skin Cancer
Authors: Bailey Howard H. , Kim KyungMann , Verma Ajit K. , Sielaff Karen , Larson Paul O. , Snow Stephen , Lenaghan Theresa , Viner Jaye L. , Douglas Jeff , Dreckschmidt Nancy E. , Hamielec Mary , Pomplun Marcy , Sharata Harry H. , Puchalsky David , Berg Eric R. , Havighurst Thomas C. , Carbone Paul P. 
Published: January 2010

AbstractPreclinical studies have shown that the inhibition of ornithine decarboxylase (ODC) by α-difluoromethylornithine (DFMO) and resultant decreases in tissue concentrations of polyamines (putrescine and spermidine) prevents neoplastic developments in many tissue types. Clinical studies of oral DFMO at 500 mg/m2/day revealed it to be safe and tolerable and resulted in significant inhibition of phorbol ester–induced skin ODC activity. Two hundred and ninety-one participants (mean age, 61 years; 60% male) with a history of prior nonmelanoma skin cancer (NMSC; mean, 4.5 skin cancers) were randomized to oral DFMO (500 mg/m2/day) or placebo for 4 to 5 years. There was a trend toward a history of more prior skin cancers in subjects randomized to placebo, but all other characteristics including sunscreen and nonsteroidal anti-inflammatory drug use were evenly distributed. Evaluation of 1,200 person-years of follow-up revealed a new NMSC rate of 0.5 events/person/year. The primary end point, new NMSCs, was not significantly different between subjects taking DFMO and placebo (260 versus 363 cancers, P = 0.069, two-sample t test). Evaluation of basal cell (BCC) and squamous cell cancers separately revealed very little difference in squamous cell cancer between treatment groups but a significant difference in new BCC (DFMO, 163 cancers; placebo, 243 cancers; expressed as event rate of 0.28 BCC/person/year versus 0.40 BCC/person/year, P = 0.03). Compliance with DFMO was &gt;90% and it seemed to be well tolerated with evidence of mild ototoxicity as measured by serial audiometric examination when compared with placebo subjects. The analysis of normal skin biopsies revealed a significant (P &lt; 0.05) decrease in 12-0-tetradecanoylphorbol-13-acetate–induced ODC activity (month 24, 36, and 48) and putrescine concentration (month 24 and 36 only) in DFMO subjects. Subjects with a history of skin cancer taking daily DFMO had an insignificant reduction (P = 0.069) in new NMSC that was predominantly due to a marked reduction in new BCC. Based on these data, the potential of DFMO, alone or in combination, to prevent skin cancers should be explored further. Cancer Prev Res; 3(1); 35–47
Chemopreventive Effects of Frondanol A5, a Cucumaria frondosa Extract, against Rat Colon Carcinogenesis and Inhibition of Human Colon Cancer Cell Growth
Authors: Janakiram Naveena B. , Mohammed Altaf , Zhang Yuting , Choi Chang-In , Woodward Carl , Collin Peter , Steele Vernon E. , Rao Chinthalapally V. 
Published: January 2010

Abstract
Sea cucumber extracts have been widely used to treat individuals with inflammatory conditions in East Asia. The present study has been designed to test potential colon cancer–preventive properties of Frondanol A5, a glycolipid extract from the sea cucumber, Cucumaria frondosa, using in vivo and in vitro models of colon cancer. Chemopreventive efficacy of Frondanol A5 was evaluated on azoxymethane-induced rat colon carcinogenesis using colonic aberrant crypt foci (ACF) as efficacy marker. At 7 weeks of age, groups of rats (12 per group) were fed the AIN-76A diet, and ACFs were induced by azoxymethane (15 mg/kg body weight). Three days after azoxymethane treatment, rats were fed with the diets containing 0, 150, and 450 ppm of Frondanol A5 and continued on the diets for 8 weeks, at which time ACFs were evaluated. Expression levels of proliferating cell nuclear antigen and p21WAF1/CIP1 were determined in ACFs. Further, Frondanol A5 (10-120 μg/mL) was studied for its growth-inhibitory and apoptotic effects in the HCT-116 cell line. Dietary administration of 150 and 450 ppm of Frondanol A5 significantly suppressed azoxymethane-induced total colonic ACF formation, approximately 34% to 55% (P &lt; 0.01 to P &lt; 0.0001), and multicrypt aberrant foci (48-68.5%, P &lt; 0.0001) in a dose-dependent manner. ACFs in rats treated with Frondanol A5 showed significant upregulation of p21WAF1/CIP1 and downregulation of proliferating cell nuclear antigen compared with control group. Frondanol A5 showed growth inhibition at S and G2-M phase with a decrease in Cdc25c and an increase in p21WAF1/CIP with significant apoptosis associated with H2AX phosphorylation and caspase-2 cleavage in HCT116 cells. Overall, Frondanol A5 exhibits potential chemopreventive properties for colon carcinogenesis, which suggests further development of this sea cucumber extract. Cancer Prev Res; 3(1); 82–91
Basal Cell Carcinoma Chemoprevention with Nonsteroidal Anti-inflammatory Drugs in Genetically Predisposed PTCH1+/− Humans and Mice
Authors: Tang Jean Y. , Aszterbaum Michelle , Athar Mohammad , Barsanti Franco , Cappola Carol , Estevez Nini , Hebert Jennifer , Hwang Jimmy , Khaimskiy Yefim , Kim Arianna , Lu Ying , So Po-Lin , Tang Xiuwei , Kohn Michael A. , McCulloch Charles E. , Kopelovich Levy , Bickers David R. , Epstein Ervin H. 
Published: January 2010

Abstract
In vitro and epidemiologic studies favor the efficacy of nonsteroidal anti-inflammatory drugs (NSAID) in preventing skin squamous photocarcinogenesis, but there has been relatively little study of their efficacy in preventing the more common skin basal cell carcinoma (BCC) carcinogenesis. We first compared the relative anti-BCC effects of genetic deletion and NSAID pharmacologic inhibition of cyclooxygenase (COX) enzymes in the skin of Ptch1+/− mice. We then assessed the effects of celecoxib on the development of BCCs in a 3-year, double-blinded, randomized clinical trial in 60 (PTCH1+/−) patients with the basal cell nevus syndrome. In Ptch1+/− mice, genetic deletion of COX1 or COX2 robustly decreased (75%; P &lt; 0.05) microscopic BCC tumor burden, but pharmacologic inhibition with celecoxib reduced microscopic BCCs less efficaciously (35%; P &lt; 0.05). In the human trial, we detected a trend for oral celecoxib reducing BCC burden in all subjects (P = 0.069). Considering only the 60% of patients with less severe disease (&lt;15 BCCs at study entry), celecoxib significantly reduced BCC number and burden: subjects receiving placebo had a 50% increase in BCC burden per year, whereas subjects in the celecoxib group had a 20% increase (Pdifference = 0.024). Oral celecoxib treatment inhibited BCC carcinogenesis in PTCH1+/− mice and had a significant anti-BCC effect in humans with less severe disease. Cancer Prev Res; 3(1); OF1–11