bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and Evaluation of an International Service Learning Program for Nursing Students
Authors: Curtin Alicia J. , Martins Diane C. , Schwartz‐Barcott Donna , DiMaria Lisa , Ogando Béliga Milagros Soler 
Published: April 2013

AbstractObjectives(1) Using Riner's framework, the development of an international service learning program in the Dominican Republic (DR) for Baccalaureate nursing students will be described, and (2) an initial impact of the students' experiences will be examined.Design and SampleA qualitative descriptive research design was used to examine its impact. The international service learning program included (1) didactic (five, 2 hr and one full day educational sessions) prior to (2) immersion (2 weeks in country), and (3) posttrip debriefing session. Ten females, senior nursing students participated in the program. Students' daily journals were examined using thematic analysis.ResultsFive major themes that emerged were as follows adapting physically, encountering frustration in their inability to fully meet patients' needs, increasing confidence in speaking Spanish and assessing health problems, and increasing cultural awareness. Students were descriptive regarding their daily activities, and did some, but limited, critical reflection.ConclusionsModels of reflection need to be explored to select the most appropriate technique to facilitate students' critical reflection in meeting the goals and objectives of the experience. Curriculum integration of global learning, social consciousness, and global cultural competence development is needed.
Population Density, Distance to Public Transportation, and Health of Women in Low‐Income Neighborhoods
Authors: DeGuzman Pamela B. , Merwin Elizabeth I. , Bourguignon Cheryl 
Published: April 2013

AbstractObjectivesThe purpose of this research was to determine the impact of two neighborhood walkability (the extent to which the built environment is pedestrian friendly) metrics on health outcomes of women living in low‐income urban neighborhoods, both before and after accounting for individual and neighborhood factors.Design and SampleA cross‐sectional, retrospective design was used. The sample of 1800 low‐income women was drawn from Welfare, Children and Families: A Three‐City Study (a study of low‐income women from three U.S. cities).MeasuresUsing multilevel modeling and geographic information systems, the study sought to determine the effect of distance to public transportation and residential density on health status, mental health symptoms, and health‐related limitations.ResultsNo significant relationship was found between the two walkability metrics and health outcomes. Instead, neighborhood problems that affect crime and safety impacted health status and mental health symptoms.ConclusionsAs cities make changes to the built environment with the hope of affecting residents' health outcomes, public health nurses need to be aware that changing walkability characteristics in a neighborhood may not affect the health of residents of high crime, low‐income neighborhoods. Without first addressing neighborhood crime, efforts to improve walkability in low‐income neighborhoods may fail.
Socioeconomic Factors Affecting Infant Sleep‐Related Deaths in St. Louis
Authors: Hogan Cathy 
Published: April 2013

AbstractObjectiveThough the Back to Sleep Campaign that began in 1994 caused an overall decrease in sudden infant death syndrome (SIDS) rates, racial disparity has continued to increase in St. Louis. Though researchers have analyzed and described various sociodemographic characteristics of SIDS and infant deaths by unintentional suffocation in St. Louis, they have not simultaneously controlled for contributory risk factors to racial disparity such as race, poverty, maternal education, and number of children born to each mother (parity). To determine whether there is a relationship between maternal socioeconomic factors and sleep‐related infant death.Design and SampleThis quantitative case‐control study used secondary data collected by the Missouri Department of Health and Senior Services between 2005 and 2009. The sample includes matched birth/death certificates and living birth certificates of infants who were born/died within time frame.MeasuresDescriptive analysis, Chi‐square, and logistic regression.ResultsThe controls were birth records of infants who lived more than 1 year. Chi‐square and logistic regression analyses confirmed that race and poverty have significant relationships with infant sleep‐related deaths.ConclusionsThe social significance of this study is that the results may lead to population‐specific modifications of prevention messages that will reduce infant sleep‐related deaths.
Immunobiology of Plasmodium in liver and brain
Authors: Frevert U. , Nacer A. 
Published: April 2013

SummaryMalaria remains one of the most serious health problems globally, but our understanding of the biology of the parasite and the pathogenesis of severe disease is still limited. Multiple cellular effector mechanisms that mediate parasite elimination from the liver have been described, but how effector cells use classical granule‐mediated cytotoxicity to attack infected hepatocytes and how cytokines and chemokines spread via the unique fluid pathways of the liver to reach the parasites over considerable distances remains unknown. Similarly, a wealth of information on cerebral malaria (CM), one of the most severe manifestations of the disease, was gained from post‐mortem analyses of human brain and murine disease models, but the cellular processes that ultimately cause disease are not fully understood. Here, we discuss how imaging of the local dynamics of parasite infection and host response as well as consideration of anatomical and physiological features of liver and brain can provide a better understanding of the initial asymptomatic hepatic phase of the infection and the cascade of events leading to CM. Given the increasing drug resistance of both parasite and vector and the unavailability of a protective vaccine, the urgency to reduce the tremendous morbidity and mortality associated with severe malaria is obvious.
Expression of Cyclins and Cyclin‐Dependent Kinase Inhibitors in Granulosa Cells from Bovine Ovary
Authors: Shimizu T , Hirai Y , Miyamoto A 
Published: April 2013

ContentsThe regulation of granulosa cell proliferation is complex, and it is essential for normal follicular development in mammals. The aim of this study was to examine the expression of cyclins and their inhibitors in the granulosa cells of follicles at different developmental stages. Follicles were classified into three groups: oestrogen‐inactive dominant follicles (EIDs), oestrogen‐active dominant follicles (EADs) and pre‐ovulatory follicles (POs). The expression of CCND2 (cyclin D2) mRNA was significantly higher in granulosa cells from EADs and POs than in those from EIDs. The expression of CCND3 (cyclin D3) mRNA was significantly higher in granulosa cells from EADs than in those from other follicles. CCND1 (cyclin D1), CCNE1 (cyclin E1) and CCNE2 (cyclin E2) mRNA expression did not differ among the different follicular stages. The expression of CDKN1A (p21cip1) and CDKN1B (p27kip1) mRNA was significantly higher in granulosa cells from EIDs and POs, respectively, than in those from other follicles. Expression of CDKN2D (p19INK4d) mRNA did not differ among the different follicular stages. Taken together, our study suggested that cyclins and their inhibitors are associated with granulosa cell proliferation at specific follicular developmental stages.
Ambient wood smoke, traffic pollution and adult asthma prevalence and severity
Authors: Bui D. Son , Burgess John A. , Matheson Melanie C. , Erbas Bircan , Perret Jennifer , Morrison Stephen , Giles Graham G. , Hopper John L. , Thomas Paul S. , Markos James , Abramson Michael J. , Walters E. Haydn , Dharmage Shyamali C. 
Published: April 2013

AbstractBackground and objectiveThe impact of ambient wood smoke and traffic‐related air pollution on adult asthma has not been well studied. This paper aims to investigate associations between exposure to ambient wood smoke, traffic‐related air pollution and current asthma/asthma severity in middle age, and whether any associations are modified by atopic status.MethodsUsing data from the Tasmanian Longitudinal Health Study, associations between ambient wood smoke and two indices of traffic‐related air pollution (frequency of heavy vehicles near the home and frequency of intense traffic noise) and current asthma/asthma severity were investigated. Unconditional logistic regression to examine current asthma and ordinal logistic regression to examine asthma severity was used.ResultsFor asthmatics, both exposure to ambient wood smoke (odds ratio 1.11; 95% confidence interval 1.02–1.20) and being frequently exposed to heavy vehicles (odds ratio 1.80; 95% confidence interval 1.09–2.96) were associated with increased asthma severity. Neither association varied by atopic status.ConclusionsIn middle‐aged adults, ambient wood smoke and traffic pollution were associated with increased asthma severity. These findings suggest that avoiding or limiting exposure to traffic pollution and wood smoke may help to reduce asthma. Future studies to replicate this finding are recommended and should examine specific biological mechanisms for this effect.
Cretaceous and Cenozoic cooling history of the eastern Qilian Shan, north‐eastern margin of the Tibetan Plateau: evidence from apatite fission‐track analysis
Authors: Baotian Pan , Qingyang Li , Xiaofei Hu , Haopeng Geng , Zibian Liu , Shaofei Jiang , Wanming Yuan 
Published: April 2013

AbstractThe exhumation history and tectonic evolution of the Qilian Shan at the north‐eastern margin of the Tibetan Plateau has been widely debated. Here, we present apatite fission‐track (AFT) data for 12 Ordovician granodiorite samples along a vertical transect in the eastern Qilian Shan. These thermochronometry data indicate that the eastern Qilian Shan experienced a three‐stage cooling history, including: (i) rapid initial cooling in the late Cretaceous; (ii) a stage of quasi isothermal quiescence from ~ 80 to 24 Ma; and (iii) rapid subsequent cooling beginning in the early Miocene. The inferred cooling rates for the three stages are 6.8 ± 4.9 °C Ma−1, 0.6 ± 0.2 °C Ma−1 and 2.7 ± 0.9 °C Ma−1 respectively (±1 σ). Assuming a geothermal gradient of 25 °C km−1, the exhumation rates for the three stages are 0.27 ± 0.20 mm a−1, 0.017 ± 0.007 mm a−1 and 0.11 ± 0.04 mm a−1 respectively (±1 σ). We suggest that the late Cretaceous cooling records collision of the Lhasa block with the Eurasian continent and that the Miocene cooling represents uplift/exhumation of the Qilian Shan.
Steady-State Pharmacokinetics of Oral Voriconazole and Its Primary Metabolite,
N
-Oxide Voriconazole, Pre- and Post-Autologous Peripheral Stem Cell Transplantation
Authors: Amsden Jarrett R. , Gubbins Paul O. , McConnell Scott , Anaissie Elias 
Published: April 2013

ABSTRACT

Voriconazole (VCZ) is frequently utilized for prevention and treatment of invasive fungal infections in peripheral stem cell transplant (PSCT) patients. We performed an open-label pharmacokinetic study to compare VCZ and
N
-oxide voriconazole (
N
-oxide VCZ) pharmacokinetics in patients pre- and post-PSCT. Ten patients completed both sampling periods. The pharmacokinetics of VCZ were unchanged; however, those of
N
-oxide VCZ were significantly different pre- and post-PSCT.
Dormancy Is Not Necessary or Sufficient for Bacterial Persistence
Authors: Orman Mehmet A. , Brynildsen Mark P. 
Published: April 2013

ABSTRACT
The antibiotic tolerances of bacterial persisters have been attributed to transient dormancy. While persisters have been observed to be growth inhibited prior to antibiotic exposure, we sought to determine whether such a trait was essential to the phenotype. Furthermore, we sought to provide direct experimental evidence of the persister metabolic state so as to determine whether the common assumption of metabolic inactivity was valid. Using fluorescence-activated cell sorting (FACS), a fluorescent indicator of cell division, a fluorescent measure of metabolic activity, and persistence assays, we found that bacteria that are rapidly growing prior to antibiotic exposure can give rise to persisters and that a lack of replication or low metabolic activity prior to antibiotic treatment simply increases the likelihood that a cell is a persister. Interestingly, a lack of significant growth or metabolic activity does not guarantee persistence, as the majority of even “dormant” subpopulations (>99%) were not persisters. These data suggest that persistence is far more complex than dormancy and point to additional characteristics needed to define the persister phenotype.
Gentamicin-Loaded Borate Bioactive Glass Eradicates Osteomyelitis Due to Escherichia coli in a Rabbit Model
Authors: Xie Zongping , Cui Xu , Zhao Cunju , Huang Wenhai , Wang Jianqiang , Zhang Changqing 
Published: April 2013

ABSTRACT

The treatment of osteomyelitis induced by Gram-negative bacilli is rarely reported in the literature. This study established a rabbit tibia model of osteomyelitis induced by the Gram-negative bacillus
Escherichia coli
. Using this model, pellets composed of a chitosan-bonded mixture of borate bioactive glass and gentamicin were evaluated
in vitro
and
in vivo
for the treatment of osteomyelitis induced by
Escherichia coli
. Our results showed that the pellets in phosphate-buffered saline released gentamicin continuously over 26 days. Without the simultaneous use of a systemic antibiotic, the implantation of the gentamicin-loaded pellets into the osteomyelitis region of the tibia resulted in the eradication of 81.82% of infections, as determined by microbiological, histological and radiographic evaluation, and supported the ingrowth of new bone into the tibia defects after 6 weeks of implantation. The results indicate that the gentamicin-loaded borate bioactive glass implant, combining sustained drug release with the ability to support new bone formation, could provide a method for treating osteomyelitis induced by Gram-negative bacilli.
In Vitro
and
In Vivo
Antimalarial Efficacies of Optimized Tetracyclines
Authors: Draper Michael P. , Bhatia Beena , Assefa Haregewein , Honeyman Laura , Garrity-Ryan Lynne K. , Verma Atul K. , Gut Jiri , Larson Kelley , Donatelli Janice , Macone Ann , Klausner Kevin , Leahy Raina G. , Odinecs Aleksandrs , Ohemeng Kwasi , Rosenthal Philip J. , Nelson Mark L. 
Published: April 2013

ABSTRACT

With increasing resistance to existing antimalarials, there is an urgent need to discover new drugs at affordable prices for countries in which malaria is endemic. One approach to the development of new antimalarial drugs is to improve upon existing antimalarial agents, such as the tetracyclines. Tetracyclines exhibit potent, albeit relatively slow, action against malaria parasites, and doxycycline is used for both treatment (with other agents) and prevention of malaria. We synthesized 18 novel 7-position modified tetracycline derivatives and screened them for activity against cultured malaria parasites. Compounds with potent
in vitro
activity and other favorable drug properties were further tested in a rodent malaria model. Ten compounds inhibited the development of cultured
Plasmodium falciparum
with a 50% inhibitory concentration (IC
50
) after 96 h of incubation of <30 nM, demonstrating activity markedly superior to that of doxycycline (IC
50
at 96 h of 320 nM). Most compounds showed little mammalian cell cytotoxicity and no evidence of
in vitro
phototoxicity. In a murine
Plasmodium berghei
model, 13 compounds demonstrated improved activity relative to that of doxycycline. In summary, 7-position modified tetracyclines offer improved activity against malaria parasites compared to doxycycline. Optimized compounds may allow lower doses for treatment and chemoprophylaxis. If safety margins are adequate, dosing in children, the group at greatest risk for malaria in countries in which it is endemic, may be feasible.
Characterization and Functional Analysis of AatB, a Novel Autotransporter Adhesin and Virulence Factor of Avian Pathogenic Escherichia coli
Authors: ZhuGe Xiangkai , Wang Shaohui , Fan Hongjie , Pan Zihao , Ren Jianluan , Yi Li , Meng Qingmei , Yang Xuqiu , Lu Chengping , Dai Jianjun 
Published: April 2013

ABSTRACT

Autotransporter (AT) proteins constitute a large family of extracellular proteins that contribute to bacterial virulence. A novel AT adhesin gene,
aatB
, was identified in avian pathogenic
Escherichia coli
(APEC) DE205B via genomic analyses. The open reading frame of
aatB
was 1,017 bp, encoding a putative 36.3-kDa protein which contained structural motifs characteristic for AT proteins: a signal peptide, a passenger domain, and a translocator domain. The predicted three-dimensional structure of AatB consisted of two distinct domains, the C-terminal β-barrel translocator domain and an N-terminal passenger domain. The prevalence analyses of
aatB
in APEC indicated that
aatB
was detected in 26.4% (72/273) of APEC strains and was strongly associated with phylogenetic groups D and B2. Quantitative real-time reverse transcription-PCR analyses revealed that AatB expression was increased during infection
in vitro
and
in vivo
. Moreover, AatB could elicit antibodies in infected ducks, suggesting that AatB is involved in APEC pathogenicity. Thus, APEC DE205B strains with a mutated
aatB
gene and mutated strains complemented with the
aatB
gene were constructed. Inactivation of
aatB
resulted in a reduced capacity to adhere to DF-1 cells, defective virulence capacity
in vivo
, and decreased colonization capacity in lung during systemic infection compared with the capacities of the wild-type strain. Furthermore, these capacities were restored in the complementation strains. These results indicated that AatB makes a significant contribution to APEC virulence through bacterial adherence to host tissues
in vivo
and
in vitro
. In addition, biofilm formation assays with strain AAEC189 expressing AatB indicated that AatB mediates biofilm formation.
Heme Catabolism by Heme Oxygenase-1 Confers Host Resistance to Mycobacterium Infection
Authors: Silva-Gomes Sandro , Appelberg Rui , Larsen Rasmus , Soares Miguel Parreira , Gomes Maria Salomé 
Published: April 2013

ABSTRACTHeme oxygenases (HO) catalyze the rate-limiting step of heme degradation. The cytoprotective action of the inducible HO-1 isoform, encoded by theHmox1gene, is required for host protection against systemic infections. Here we report that upregulation of HO-1 expression in macrophages (Mϕ) is strictly required for protection against mycobacterial infection in mice. HO-1-deficient (Hmox1−/−) mice are more susceptible to intravenousMycobacterium aviuminfection, failing to mount a protective granulomatous response and developing higher pathogen loads, than infected wild-type (Hmox1+/+) controls. Furthermore,Hmox1−/−mice also develop higher pathogen loads and ultimately succumb when challenged with a low-dose aerosol infection withMycobacterium tuberculosis. The protective effect of HO-1 acts independently of adaptive immunity, as revealed inM. avium-infectedHmox1−/−versusHmox1+/+SCID mice lacking mature B and T cells. In the absence of HO-1, heme accumulation acts as a cytotoxic pro-oxidant in infected Mϕ, an effect mimicked by exogenous heme administration toM. avium-infected wild-type Mϕin vitroor to micein vivo. In conclusion, HO-1 prevents the cytotoxic effect of heme in Mϕ, contributing critically to host resistance toMycobacteriuminfection.
Lipopolysaccharide Modifications of a Cholera Vaccine Candidate Based on Outer Membrane Vesicles Reduce Endotoxicity and Reveal the Major Protective Antigen
Authors: Leitner Deborah R. , Feichter Sandra , Schild-Prüfert Kristina , Rechberger Gerald N. , Reidl Joachim , Schild Stefan 
Published: April 2013

ABSTRACT

The causative agent of the life-threatening gastrointestinal infectious disease cholera is the Gram-negative, facultative human pathogen
Vibrio cholerae
. We recently started to investigate the potential of outer membrane vesicles (OMVs) derived from
V. cholerae
as an alternative approach for a vaccine candidate against cholera and successfully demonstrated the induction of a long-lasting, high-titer, protective immune response upon immunization with OMVs using the mouse model. In this study, we present immunization data using lipopolysaccharide (LPS)-modified OMVs derived from
V. cholerae
, which allowed us to improve and identify the major protective antigen of the vaccine candidate. Our results indicate that reduction of endotoxicity can be achieved without diminishing the immunogenic potential of the vaccine candidate by genetic modification of lipid A. Although the protective potential of anti-LPS antibodies has been suggested many times, this is the first comprehensive study that uses defined LPS mutants to characterize the LPS-directed immune response of a cholera vaccine candidate in more detail. Our results pinpoint the O antigen to be the essential immunogenic structure and provide a protective mechanism based on inhibition of motility, which prevents a successful colonization. In a detailed analysis using defined antisera, we can demonstrate that only anti-O antigen antibodies, but not antibodies directed against the major flagellar subunit FlaA or the most abundant outer membrane protein, OmpU, are capable of effectively blocking the motility by binding to the sheathed flagellum and provide protection in a passive immunization assay.