bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fimbrial Profiles Predict Virulence of Uropathogenic Escherichia coli Strains: Contribution of Ygi and Yad Fimbriae
Authors: Spurbeck Rachel R. , Stapleton Ann E. , Johnson James R. , Walk Seth T. , Hooton Thomas M. , Mobley Harry L. T. 
Published: September 2011

ABSTRACT

Escherichia coli
, a cause of ∼90% of urinary tract infections (UTI), utilizes fimbrial adhesins to colonize the uroepithelium. Pyelonephritis isolate
E. coli
CFT073 carries 12 fimbrial operons, 5 of which have never been studied. Using multiplex PCR, the prevalence of these 12 and 3 additional fimbrial types was determined for a collection of 303
E. coli
isolates (57 human commensal, 32 animal commensal, 54 asymptomatic bacteriuria, 45 complicated UTI, 38 uncomplicated cystitis, and 77 pyelonephritis). The number of fimbrial types per
E. coli
isolate was distributed bimodally: those with low (3.2 ± 1.1) and those with high (8.3 ± 1.3) numbers of fimbrial types (means ± standard errors of the means). The fimbrial genes
ygiL
,
yadN
,
yfcV
, and
c2395
were significantly more prevalent among urine isolates than human commensal isolates. The effect of deletion of Ygi and Yad fimbrial operons on growth, motility, biofilm formation, adherence to immortalized human epithelial cells, and pathogenesis in the mouse model of UTI was examined. Yad fimbriae were necessary for wild-type levels of adherence to a bladder epithelial cell line and for biofilm formation. Deletion of these fimbrial genes increased motility. Ygi fimbriae were necessary for wild-type levels of adherence to a human embryonic kidney cell line, biofilm formation, and
in vivo
fitness in the urine and kidneys. Complementation of each fimbrial mutant restored wild-type levels of motility, biofilm formation, adherence and, for
ygi
,
in vivo
fitness. A double deletion strain, Δ
ygi Δyad
, was attenuated in the urine, bladder, and kidneys in the mouse model, demonstrating that these fimbriae contribute to uropathogenesis.
Inhibition of Indoleamine 2,3-Dioxygenase Activity by Levo-1-Methyl Tryptophan Blocks Gamma Interferon-Induced Chlamydia trachomatis Persistence in Human Epithelial Cells
Authors: Ibana Joyce A. , Belland Robert J. , Zea Arnold H. , Schust Danny J. , Nagamatsu Takeshi , AbdelRahman Yasser M. , Tate David J. , Beatty Wandy L. , Aiyar Ashok A. , Quayle Alison J. 
Published: September 2011

ABSTRACT

Gamma interferon (IFN-γ) induces expression of the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase (IDO1) in human epithelial cells, the permissive cells for the obligate intracellular bacterium
Chlamydia trachomatis
. IDO1 depletes tryptophan by catabolizing it to kynurenine with consequences for
C. trachomatis
, which is a tryptophan auxotroph.
In vitro
studies reveal that tryptophan depletion can result in the formation of persistent (viable but noncultivable) chlamydial forms. Here, we tested the effects of the IDO1 inhibitor, levo-1-methyl-tryptophan (L-1MT), on IFN-γ-induced
C. trachomatis
persistence. We found that addition of 0.2 mM L-1MT to IFN-γ-exposed infected HeLa cell cultures restricted IDO1 activity at the mid-stage (20 h postinfection [hpi]) of the chlamydial developmental cycle. This delayed tryptophan depletion until the late stage (38 hpi) of the cycle. Parallel morphological and gene expression studies indicated a consequence of the delay was a block in the induction of
C. trachomatis
persistence by IFN-γ. Furthermore, L-1MT addition allowed
C. trachomatis
to undergo secondary differentiation, albeit with limited productive multiplication of the bacterium. IFN-γ-induced persistent infections in epithelial cells have been previously reported to be more resistant to doxycycline than normal productive infections
in vitro
. Pertinent to this observation, we found that L-1MT significantly improved the efficacy of doxycycline in clearing persistent
C. trachomatis
forms. It has been postulated that persistent forms of
C. trachomatis
may contribute to chronic chlamydial disease. Our findings suggest that IDO1 inhibitors such as L-1MT might provide a novel means to investigate, and potentially target, persistent chlamydial forms, particularly in conjunction with conventional therapeutics.
Complete Genome Sequence of Alicyclobacillus acidocaldarius Strain Tc-4-1
Authors: Chen Yaping , He Yongzhi , Zhang Bing , Yang Jin , Li Wenjie , Dong Zhiyang , Hu Songnian 
Published: September 2011

ABSTRACT

Alicyclobacillus acidocaldarius
strain Tc-4-1 was initially isolated from a hot spring in Tengchong, China. This organism is both thermophilic and acidophilic. It can produce heat- and acid-stable enzymes, such as amylase and esterase, which may be important in industry. Here we report the whole genome sequence of the strain.
Genome Sequence of an Ammonia-Oxidizing Soil Archaeon, “Candidatus Nitrosoarchaeum koreensis” MY1
Authors: Kim Byung Kwon , Jung Man-Young , Yu Dong Su , Park Soo-Je , Oh Tae Kwang , Rhee Sung-Keun , Kim Jihyun F. 
Published: September 2011

ABSTRACT

Ammonia-oxidizing archaea are ubiquitous microorganisms which play important roles in global nitrogen and carbon cycle on earth. Here we present the high-quality draft genome sequence of an ammonia-oxidizing archaeon, “
Candidatus
Nitrosopumilus koreensis” MY1, that dominated an enrichment culture of a soil sample from the rhizosphere. Its genome contains genes for survival in the rhizosphere environment as well as those for carbon fixation and ammonium oxidation to nitrite.
Inhibition of SAPK2/p38 Enhances Sensitivity to mTORC1 Inhibition by Blocking IRES-Mediated Translation Initiation in Glioblastoma
Authors: Cloninger Cheri , Bernath Andrew , Bashir Tariq , Holmes Brent , Artinian Nicholas , Ruegg Teresa , Anderson Lauren , Masri Janine , Lichtenstein Alan , Gera Joseph 
Published: September 2011

Abstract
A variety of mechanisms confer hypersensitivity of tumor cells to the macrolide rapamycin, the prototypic mTORC1 inhibitor. Several studies have shown that the status of the AKT kinase plays a critical role in determining hypersensitivity. Cancer cells in which AKT activity is elevated are exquisitely sensitive to mTORC1 inhibitors while cells in which the kinase is quiescent are relatively resistant. Our previous work has shown that a transcript-specific protein synthesis salvage pathway is operative in cells with quiescent AKT levels, maintaining the translation of crucial mRNAs involved in cell-cycle progression in the face of global eIF-4E–mediated translation inhibition. The activation of this salvage pathway is dependent on SAPK2/p38-mediated activation of IRES-dependent initiation of the cyclin D1 and c-MYC mRNAs, resulting in the maintenance of their protein expression levels. Here, we show that both genetic and pharmacologic inhibition of SAPK2/p38 in glioblastoma multiforme cells significantly reduces rapamycin-induced IRES-mediated translation initiation of cyclin D1 and c-MYC, resulting in increased G1 arrest in vitro and inhibition of tumor growth in xenografts. Moreover, we observed that the AKT-dependent signaling alterations seen in vitro are also displayed in engrafted tumors cells and were able to show that combined inhibitor treatments markedly reduced the mRNA translational state of cyclin D1 and c-MYC transcripts in tumors isolated from mice. These data support the combined use of SAPK2/p38 and mTORC1 inhibitors to achieve a synergistic antitumor therapeutic response, particularly in rapamycin-resistant quiescent AKT-containing cells. Mol Cancer Ther; 10(12); 2244–56. ©2011 AACR.
SDF-1α Induces PDGF-B Expression and the Differentiation of Bone Marrow Cells into Pericytes
Authors: Hamdan Randala , Zhou Zhichao , Kleinerman Eugenie S. 
Published: September 2011

Abstract
Platelet-derived growth factor B (PDGF-B) and its receptor, PDGFR-β, play a critical role in pericyte maturation; however, the mechanisms by which PDGF-B is upregulated in the tumor microenvironment remain unclear. We previously showed that upregulating stromal-derived factor, SDF-1α, in VEGF165-inhibited Ewing's sarcoma tumors (TC/siVEGF7-1) induced PDGF-B mRNA expression, increased infiltration and differentiation of bone marrow cells (BMC) into pericytes and, rescued tumor growth. The purpose of this study was to investigate the mechanism by which SDF-1α increased PDGF-B expression and the role of this pathway in BM-derived pericyte differentiation. We showed that SDF-1α induced expression of PDGF-B mRNA and protein both in vitro and in vivo. In contrast, inhibiting SDF-1α downregulated PDGF-B. We cloned the 2-kb pdgf-b promoter fragment and showed that SDF-1α activates PDGF-B via a transcriptional mechanism. Chromatin immunoprecipitation showed that the ELK-1 transcription factor binds to the pdgf-b promoter in response to SDF-1α. We confirmed the correlation between the SDF-1α/PDGF-B pathway and the differentiation of PDGFR-β+ BMCs into mature pericytes using an in vitro assay. These findings show that SDF-1α regulates PDGF-B expression and that this regulation plays a critical role in the differentiation of PDGFR-β+ BMCs into mature pericytes. Mol Cancer Res; 9(11); 1462–70. ©2011 AACR.
The appropriateness of single page of activation of the cardiac catheterization laboratory by emergency physician for patients with suspected ST-segment elevation myocardial infarction: a cohort study
Authors: Kim Soo Hyun , Oh Sang Hoon , Choi Seung Pill , Park Kyu Nam , Kim Young Min , Youn Chun Song 
Published: September 2011

Abstract

Background
The early use of reperfusion therapy has a significant effect on the prognosis of patients with ST-segment elevation myocardial infarction (STEMI), and it is recommended that emergency department (ED) physicians activate the cardiac catheterization laboratory (CCL) as soon as possible to treat these patients. The aim of this study was to examine the appropriateness of emergency physician activation of the CCL for patients with suspected STEMI. Inappropriate activations (i.e., false positive activations) were identified according to a variety of criteria.

Methods
All patients with emergency physician CCL activations between August 2009 and April 2011 were included in the study. False positive cases were defined according to ECG criteria and cardiologists' reviews of patients' initial clinical information.

Results
ED physicians used a STEMI page to activate the CCL 117 times. According to reviews by cardiologists, this activation was appropriate 89.8% of the time (in 105/117 cases). Truly unnecessary activation (i.e., cases in which STEMI was not identified by the cardiologists, no clear culprit coronary artery was present, no significant coronary artery disease and cardiac biomarkers were negative) occurred 5.1% of the time (in 6/117 cases).

Conclusions
CCL activation was appropriate for most patients and was unnecessary in a relatively small percentage of cases. This result supports the current recommendation for CCL activation by emergency physicians. Such early activation is a key strategy in the reduction of door-to-balloon time.
Esophageal tissue engineering: An in‐depth review on scaffold design
Authors: Tan J.Y. , Chua C.K. , Leong K.F. , Chian K.S. , Leong W.S. , Tan L.P. 
Published: September 2011

AbstractTreatment of esophageal cancer often requires surgical procedures that involve removal. The current approaches to restore esophageal continuity however, are known to have limitations which may not result in full functional recovery. In theory, using a tissue engineered esophagus developed from the patient's own cells to replace the removed esophageal segment can be the ideal method of reconstruction. One of the key elements involved in the tissue engineering process is the scaffold which acts as a template for organization of cells and tissue development. While a number of scaffolds range from traditional non‐biodegradable tubing to bioactive decellularized matrix have been proposed to engineer the esophagus in the past decade, results are still not yet favorable with many challenges relating to tissue quality need to be met improvements. The success of new esophageal tissue formation will ultimately depend on the success of the scaffold being able to meet the essential requirements specific to the esophageal tissue. Here, the design of the scaffold and its fabrication approaches are reviewed. In this paper, we review the current state of development in bioengineering the esophagus with particular emphasis on scaffold design. Biotechnol. Bioeng. 2012;109: 1–15. © 2011 Wiley Periodicals, Inc.
A monolithic lipase reactor for biodiesel production by transesterification of triacylglycerides into fatty acid methyl esters
Authors: Urban Jiri , Svec Frantisek , Fréchet Jean M.J. 
Published: September 2011

AbstractAn enzymatic reactor with lipase immobilized on a monolithic polymer support has been prepared and used to catalyze the transesterification of triacylglycerides into the fatty acid methyl esters commonly used for biodiesel. A design of experiments procedure was used to optimize the monolithic reactor with variables including control of the surface polarity of the monolith via variations in the length of the hydrocarbon chain in alkyl methacrylate monomer, time of grafting of 1‐vinyl‐4,4‐dimethylazlactone used to activate the monolith, and time used for the immobilization of porcine lipase. Optimal conditions involved the use of a poly(stearyl methacrylate‐co‐ethylene dimethacrylate) monolith, grafted first with vinylazlactone, then treated with lipase for 2 h to carry out the immobilization of the enzyme. Best conditions for the transesterification of glyceryl tributyrate included a temperature of 37°C and a 10 min residence time of the substrate in the bioreactor. The reactor did not lose its activity even after pumping through it a solution of substrate equaling 1,000 reactor volumes. This enzymatic reactor was also used for the transesterification of triacylglycerides from soybean oil to fatty acid methyl esters thus demonstrating the ability of the reactor to produce biodiesel. Biotechnol. Bioeng. 2012; 109:371–380. © 2011 Wiley Periodicals, Inc.
Facilitated diffusion of myoglobin and creatine kinase and reaction–diffusion constraints of aerobic metabolism under steady‐state conditions in skeletal muscle
Authors: Dasika S.K. , Kinsey S.T. , Locke B.R. 
Published: September 2011

AbstractThe roles of creatine kinase (CK) and myoglobin (Mb) on steady‐state facilitated diffusion and temporal buffering of ATP and oxygen, respectively, are assessed within the context of a reaction–diffusion model of muscle energetics. Comparison of the reaction–diffusion model with experimental data from a wide range of muscle fibers shows that the experimentally observed skeletal muscle fibers are generally not limited by diffusion, and the model further indicates that while some muscle fibers operate near the edge of diffusion limitation, no detectable effects of Mb and CK on the effectiveness factor, a measure of diffusion constraints, are observed under steady‐state conditions. However, CK had a significant effect on average ATP concentration over a wide range of rates and length scales within the reaction limited regime. The facilitated diffusion functions of Mb and CK become observable in the model for larger size cells with low mitochondrial volume fraction and for low boundary O2 concentration and high ATP demand, where the fibers may be limited by diffusion. From the transient analysis it may be concluded that CK primarily functions to temporally buffer ATP as opposed to facilitating diffusion while Mb has a small temporal buffering effect on oxygen but does not play any significant role in steady‐state facilitated diffusion in skeletal muscle fibers under most physiologically relevant regions. Biotechnol. Bioeng. 2012; 109:545–558. © 2011 Wiley Periodicals, Inc.
Two efficient and stable MMSE detection algorithms for the V‐BLAST system
Authors: Liu T.‐H. 
Published: September 2011

SUMMARYFor practical consideration, efficient and stable implementation of the promising vertical Bell Labs Layered Space–Time system is highly desirable. The original square‐root algorithm (SRA), proposed by Hassibi, for the minimum mean square error detection, is composed of three stages, that is, initialization, ordering, and nulling. Unlike the original SRA whose initialization stage is not completely based on unitary transformations, the three stages of our proposed algorithm #1 are all based on unitary transformations. The average number of multiplications required by our proposed algorithm #1 is about (29∕10)M3, where both the numbers of transmit and receive antennas are equal to M. In the meantime, the average number of multiplications required by the original SRA is (17∕3)M3. In addition to the stable initialization, ordering, and nulling considered by the proposed algorithm #1, our proposed algorithm #2 considers stable detection. Our proposed algorithm #2 is completely based on Givens rotations, which is to be implemented by COordinate Rotation DIgital Computer‐based hardwares. Copyright © 2011 John Wiley & Sons, Ltd.
Using observed structured teaching exercises (OSTE) to enhance hospitalist teaching during family centered rounds
Authors: Ottolini Mary , Wohlberg Rachel , Lewis Karen , Greenberg Larrie 
Published: September 2011

AbstractBACKGROUND:“Rounds” are the organizing structure for academic hospitalist‐trainee teams. Family centered rounds (FCR) are endorsed by the Institute of Medicine and by the American Academy of Pediatrics, however, rounds are often conducted in the privacy of the conference room where patients and families are not privy to the decision‐making process used to determine their diagnosis and management. Less than half of pediatric hospitalists reported conducting FCR, citing concerns about inefficiency and diminished teaching.OBJECTIVE:The aim of this study was to design and implement a faculty development program to address the need of hospitalists to efficiently teach during FCR.DESIGN:Scoring templates were developed to measure evidence‐based teaching behaviors to optimize orientation, feedback, clinical reasoning, assessing physical exam findings, and promoting resident leadership during FCR. Hospitalists were scored by Standardized Learners and Standardized Parents during 4 Observed Structured Teaching Exercises (OSTEs) before and after focused workshops.RESULTS:Fourteen of 14 hospitalist participants had 17 months ± 14 months of experience; 71% were female; none had previous training in the areas proposed in the study. The differences between pre‐ and post‐OSTEs for the 4 stations were statistically significant (P < .0001). Particular improvements were noted in the correction of incorrect clinical reasoning (new patient diagnosis) (56% pre, 86% post) and orientation (65% pre, 95% post).CONCLUSIONS:We found incorporating OSTEs into a FCR faculty development program to be an effective strategy for improving faculty teaching behavior. Additional study is needed to determine if this strategy results in sustained improvements in conducting FCRs in real inpatient settings. Journal of Hospital Medicine 2011. © 2011 Society of Hospital Medicine
Simultaneous infection of measles and varicella‐zoster virus in a child in India
Authors: Biswas Dipankar , Yadav Kaushal , Borkakoty Biswajyoti , Mahanta Jagadish 
Published: September 2011

AbstractSimultaneous occurrence of measles and chickenpox in a single individual is a rare event despite the fact that each of these infections alone is very common. The clinical presentation and molecular characterization of a dual infection caused by measles and Varicella‐Zoster virus (VZV) in a 3‐year female child is reported for the first time from India. The child presented with high fever, cough, cervical lymphadenopathy, and maculopapular rash followed by vesicular skin rash. The child was not immunized against measles and chickenpox. The viral nucleic acids extracted from the clinical specimen were subjected to PCR‐Sequencing for confirmation of a dual infection with measles and VZV. The PCR and sequence analysis from the throat swab samples confirmed the coinfection of wild‐type measles (genotype D4) and Varicella‐Zoster virus (PstI+ BglI+). The measles virus RNA and VZV DNA could be detected successfully from a single specimen of a throat swab. The case recovered uneventfully. Dual infection with measles and VZV does occur but may be underreported in the literature. J. Med. Virol. 83:2004–2007, 2011. © 2011 Wiley‐Liss, Inc.
HBV DNA suppression in HBeAg‐positive chronic hepatitis B patients treated with peginterferon or placebo
Authors: Hansen Bettina E. , Rijckborst Vincent , ter Borg Martijn J. , Janssen Harry L.A. 
Published: September 2011

AbstractThe aim of the present study was to compare the decline of HBV DNA during peginterferon (PEG‐IFN) therapy with spontaneous HBV DNA decline in placebo‐treated patients with hepatitis B e antigen (HBeAg)‐positive chronic hepatitis B. A total of 136 patients who participated in a randomized trial were treated with PEG‐IFN alfa‐2b for 52 weeks. These patients were compared with 167 patients who received a placebo for 48 weeks using linear mixed regression analysis. Response was defined as loss of HBeAg at the end of treatment (EOT). Overall, decline of HBV DNA at the EOT was significantly greater in the PEG‐IFN group than in the placebo group (mean decline 2.3 log vs. 1.0 log, P < 0.001) and varied according to HBV genotype. Viral suppression was greater in the PEG‐IFN group from week 4 throughout the entire treatment period (P < 0.001). The response rate was 32% for the PEG‐IFN group and 11% for the placebo group (P < 0.001). Among responders, HBV DNA decline was greater for patients treated with PEG‐IFN than with a placebo: the mean difference in HBV DNA decline was 0.7 log (P = 0.001) at 4 weeks and 2 log (P < 0.001) at the EOT. ALT flares (>5 times the upper limit) were associated with a greater HBV DNA decline during PEG‐IFN. In conclusion, PEG‐IFN therapy resulted in a greater HBV DNA decline in positive HBeAg patients than a placebo. The decline of HBV DNA was greater in patients with HBeAg loss or who exhibited an ALT flare during PEG‐IFN than in patients with spontaneous HBeAg loss or flares during placebo therapy. J. Med. Virol. 83:1917–1923, 2011. © 2011 Wiley‐Liss, Inc.
The impact of prophylactic salpingo‐oophorectomy on quality of life and psychological distress in women with a BRCA mutation
Authors: Finch Amy , Metcalfe Kelly A. , Chiang Jaclyn , Elit Lorraine , McLaughlin John , Springate Caitlin , Esplen Mary Jane , Demsky Rochelle , Murphy Joan , Rosen Barry , Narod Steven A. 
Published: September 2011

AbstractObjectivesThe objective of this study was to measure the impact of prophylactic salpingo‐oophorectomy on health‐related quality of life and psychological distress in women.MethodsWomen who underwent prophylactic salpingo‐oophorectomy between August 20, 2003 and June 26, 2008 because of a BRCA1 or BRCA2 mutation were invited to participate. Participants completed three questionnaires (SF‐12® Health Survey, Brief Symptom Inventory and the Impact of Events Scale) before prophylactic surgery and again 1 year after surgery. Measures of health‐related quality of life, of general psychological distress and of ovarian cancer worry before and after surgery were compared.ResultsFew women who underwent salpingo‐oophorectomy experienced a worsening in physical or mental health functioning after salpingo‐oophorectomy. On average, women experienced less ovarian cancer‐specific worry after surgery; 34.3% experienced moderate to severe ovarian cancer‐specific distress before surgery, compared with 18.6% after surgery.ConclusionsFor most women, physical and mental health‐related quality of life did not deteriorate after prophylactic salpingo‐oophorectomy, and they were less worried about ovarian cancer. A subset of women continued to experience moderate to severe cancer‐specific distress. Identification of these women is important in order to provide continued counseling and support. Copyright © 2011 John Wiley & Sons, Ltd.