bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of agr dysfunction on virulence profiles and infections associated with a novel methicillin-resistant Staphylococcus aureus (MRSA) variant of the lineage ST1-SCCmec IV
Authors: Ferreira Fabienne Antunes , Souza Raquel Rodrigues , de Sousa Moraes Bruno , de Amorim Ferreira Ana Maria , Américo Marco Antônio , Fracalanzza Sérgio Eduardo Longo , dos Santos Silva Couceiro José Nelson , Sá Figueiredo Agnes Marie 
Published: April 2013

AbstractBackgroundA novel variant of the ST1-SCCmecIV methicillin-resistantStaphylococcus aureus(MRSA) lineage, mostly associated with nosocomial bloodstream infections (BSI), has emerged in Rio de Janeiro. Bacterial biofilm has been considered a major virulence factor in central venous catheter-associated BSI. The mechanisms involved in biofilm formation/accumulation are multifactorial and complex. Studies have suggested that biofilm production was affectedin vitroand vivo foragr-null mutants ofS. aureus.ResultsThe impact of naturally occurring inhibition ofagrsignaling on virulence profiles and infections associated with the ST1 variant was investigated.agrdysfunction was detected in a significant percentage (13%) of the isolates with concomitant increase in biofilm accumulationin vitroandin vivo, and enhanced ability to adhere to and invade airway cells. The biofilm formed by these ST1 isolates wasica-independent and proteinaceous in nature. In fact, the improved colonization properties were paralleled by an increased expression of the biofilm-associated genesfnbA,spaandsasG. The transcription ofsarA, a positive regulator ofagr, was two-times reduced for theagr-dysfunctional MRSA. Remarkably, theagrinhibition was genetically stable. Indeed,agr-dysfunctional isolates succeed to colonize and cause both acute and chronic infections in hospitalized patients, and also to effectively accumulate biofilm in a mouse subcutaneous catheter implant model.ConclusionThe ability ofagr-dysfunctional isolates to cause infections in humans and to form biofilm in the animal model suggests that therapeutic approaches based onagr-inactivation strategies are unlikely to be effective in controlling human-device infections caused by ST1 isolates. The increased biofilm accumulation associated with the acquisition of multiple antimicrobial resistant traits might have influenced (at least in part) the expansion of this USA400 related clone in our hospitals.
Silencing of Nicotiana benthamiana Neuroblastoma-Amplified Genecauses ER stress and cell death
Authors: Lee Jae-Yong , Sarowar Sujon , Kim Hee Seung , Kim Hyeran , Hwang Inhwan , Kim Young Jin , Pai Hyun-Sook 
Published: April 2013

Abstract

Background

Neuroblastoma Amplified Gene (NAG) was identified as a gene co-amplified with the N-myc gene, whose genomic amplification correlates with poor prognosis of neuroblastoma. Later it was found that NAG is localized in endoplasmic reticulum (ER) and is a component of the syntaxin 18 complex that is involved in Golgi-to-ER retrograde transport in human cells. Homologous sequences of NAG are found in plant databases, but its function in plant cells remains unknown.

Results

Nicotiana benthamania Neuroblastoma-Amplified Gene (NbNAG) encodes a protein of 2,409 amino acids that contains the secretory pathway Sec39 domain and is mainly localized in the ER. Silencing of NbNAG by virus-induced gene silencing resulted in growth arrest and acute plant death with morphological markers of programmed cell death (PCD), which include chromatin fragmentation and modification of mitochondrial membrane potential. NbNAG deficiency caused induction of ER stress genes, disruption of the ER network, and relocation of bZIP28 transcription factor from the ER membrane to the nucleus, similar to the phenotypes of tunicamycin-induced ER stress in a plant cell. NbNAG silencing caused defects in intracellular transport of diverse cargo proteins, suggesting that a blocked secretion pathway by NbNAG deficiency causes ER stress and programmed cell death.

Conclusions
These results suggest that NAG, a conserved protein from yeast to mammals, plays an essential role in plant growth and development by modulating protein transport pathway, ER stress response and PCD.
Genome-wide identification and functional analyses of calmodulin genes in Solanaceousspecies
Authors: Zhao Yuan , Liu Wei , Xu You-Ping , Cao Jia-Yi , Braam Janet , Cai Xin-Zhong 
Published: April 2013

AbstractBackgroundCalmodulin (CaM) is a major calcium sensor in all eukaryotes. It binds calcium and modulates the activity of a wide range of downstream proteins in response to calcium signals. However, little is known about theCaMgene family inSolanaceousspecies, including the economically important species, tomato (Solanum lycopersicum), and the gene silencing model plant,Nicotiana benthamiana. Moreover, the potential function of CaM in plant disease resistance remains largely unclear.ResultsWe performed genome-wide identification ofCaMgene families inSolanaceousspecies. Employing bioinformatics approaches, multiple full-lengthCaMgenes were identified from tomato,N. benthamianaand potato (S. tuberosum) genomes, with tomato having 6CaMgenes,N. benthamianahaving 7CaMgenes, and potato having 4CaMgenes. Sequence comparison analyses showed that three tomato genes,SlCaM3/4/5, two potato genesStCaM2/3, and two sets ofN. benthamianagenes,NbCaM1/2/3/4andNbCaM5/6,encode identical CaM proteins, yet the genes contain different intron/exon organization and are located on different chromosomes. Further sequence comparisons and gene structural and phylogenetic analyses reveal thatSolanaceousspecies gained a new group ofCaMgenes during evolution. These newCaMgenes are unusual in that they contain three introns in contrast to only a single intron typical of knownCaMgenes in plants. The tomatoCaM(SlCaM) genes were found to be expressed in all organs. Prediction of cis-acting elements in 5' upstream sequences and expression analyses demonstrated thatSlCaMgenes have potential to be highly responsive to a variety of biotic and abiotic stimuli. Additionally, silencing ofSlCaM2andSlCaM6altered expression of a set of signaling and defense-related genes and resulted in significantly lower resistance toTobacco rattle virusand the oomycete pathogen,Pythium aphanidermatum.ConclusionsTheCaMgene families in theSolanaceousspecies tomato,N. benthamianaand potato were identified through a genome-wide analysis. All three plant species harbor a small set of genes that encode identical CaM proteins, which may manifest a strategy of plants to retain redundancy or enhanced quantitative gene function. In addition,Solanaceousspecies have evolved one new group ofCaMgenes during evolution.CaMgenes play important roles in plant disease resistance to a variety of pathogens.
Dipeptidyl peptidase IV inhibitor attenuates kidney injury in rat remnant kidney
Authors: Joo Kwon Wook , Kim Sejoong , Ahn Shin-young , Chin Ho Jun , Chae Dong-Wan , Lee Jeonghwan , Han Jin Suk , Na Ki Young 
Published: April 2013

Abstract

Background
The inhibition of dipeptidyl peptidase (DPP) IV shows protective effects on tissue injury of the heart, lung, and kidney. Forkhead box O (FoxO) transcriptional factors regulate cellular differentiation, growth, survival, the cell cycle, metabolism, and oxidative stress. The aims of this study were to investigate whether the DPP IV inhibitor sitagliptin could attenuate kidney injury and to evaluate the status of FoxO3a signaling in the rat remnant kidney model.

Methods
Rats were received two-step surgery of 5/6 renal mass reduction and fed on an oral dose of 200 mg/kg/day sitagliptin for 8 weeks. Before and after the administration of sitagliptin, physiologic parameters were measured. After 8 weeks of treatment, the kidneys were harvested.

Results
The sitagliptin treatment attenuated renal dysfunction. A histological evaluation revealed that glomerulosclerosis and tubulointerstitial injury were significantly decreased by sitagliptin. Sitagliptin decreased DPP IV activity and increased the renal expression of glucagon-like peptide-1 receptor (GLP-1R). The subtotal nephrectomy led to the activation of phosphatidylinositol 3-kinase (PI3K)-Akt and FoxO3a phosphorylation, whereas sitagliptin treatment reversed these changes, resulting in PI3K-Akt pathway inactivation and FoxO3a dephosphorylation. The renal expression of catalase was increased and the phosphorylation of c-Jun N-terminal kinase (JNK) was decreased by sitagliptin. Sitagliptin treatment reduced apoptosis by decreasing cleaved caspase-3 and −9 and Bax levels and decreased macrophage infiltration.

Conclusions
In rat remnant kidneys, DPP IV inhibitor attenuated renal dysfunction and structural damage. A reduction of apoptosis, inflammation and an increase of antioxidant could be suggested as a renoprotective mechanism together with the activation of FoxO3a signaling. Therefore, DPP IV inhibitors might provide a promising approach for treating CKD, but their application in clinical practice remains to be investigated.
Determinants of infant mortality in community of Gilgel Gibe Field Research Center, Southwest Ethiopia: a matched case control study
Authors: Dube Lamessa , Taha Mohammed , Asefa Henok 
Published: April 2013

Abstract

Background
Infant mortality accounts for almost 67 percent of under-five child mortality that occurs globally. An understanding of factors related to infant mortality is important to guide the development of focused and evidence-based health interventions to reduce infant deaths. But no community based studies have been conducted to identify determinants of infant mortality in Ethiopia for the past two decades. The purpose of this study is to identify determinants of infant mortality in community of Gilgel Gibe Field Research Center, Southwest Ethiopia.

Methods
A community based matched case–control study was conducted. The study covered 133 infants who died during infancy between January 2010 and February 2011 in the study area. For each case, a control with approximately same date of birth and survived his/her first year of live and alive at time data collection was selected. Conditional logistic regression method was used to identify determinant factors of infant mortality using Epi-info 3.5.1 statistical software.

Results
According to the final logistic regression model, not attending antenatal care follow-up [AOR=2.04, 95% CI:(1.04,4.02)], not using soap for hand washing before feeding child [AOR=2.50, 95% CI: (1.32,4.76)], negative perceived benefits of mother to modern treatment and prevention [AOR=2.76, 95% CI: (1.21,6.09)], small birth size [AOR=2.91, 95% CI: (1.01,8.46)] and high birth order with short birth interval [AOR=3.80, 95% CI: (1.20,11.98)] were found to be independent determinants of infant mortality.

Conclusions
Antenatal care follow-up, hand washing habit with soap before feeding child, birth size, perceived benefits of mothers to modern treatment, birth order and preceding birth interval were determinants of infant mortality.
Development, scoring, and reliability of the Microscale Audit of Pedestrian Streetscapes (MAPS)
Authors: Millstein Rachel A , Cain Kelli L , Sallis James F , Conway Terry L , Geremia Carrie , Frank Lawrence D , Chapman Jim , Van Dyck Delfien , Dipzinski Lindsay R , Kerr Jacqueline , Glanz Karen , Saelens Brian E 
Published: April 2013

Abstract

Background
Streetscape (microscale) features of the built environment can influence people’s perceptions of their neighborhoods’ suitability for physical activity. Many microscale audit tools have been developed, but few have published systematic scoring methods. We present the development, scoring, and reliability of the Microscale Audit of Pedestrian Streetscapes (MAPS) tool and its theoretically-based subscales.

Methods
MAPS was based on prior instruments and was developed to assess details of streetscapes considered relevant for physical activity. MAPS sections (route, segments, crossings, and cul-de-sacs) were scored by two independent raters for reliability analyses. There were 290 route pairs, 516 segment pairs, 319 crossing pairs, and 53 cul-de-sac pairs in the reliability sample. Individual inter-rater item reliability analyses were computed using Kappa, intra-class correlation coefficient (ICC), and percent agreement. A conceptual framework for subscale creation was developed using theory, expert consensus, and policy relevance. Items were grouped into subscales, and subscales were analyzed for inter-rater reliability at tiered levels of aggregation.

Results
There were 160 items included in the subscales (out of 201 items total). Of those included in the subscales, 80 items (50.0%) had good/excellent reliability, 41 items (25.6%) had moderate reliability, and 18 items (11.3%) had low reliability, with limited variability in the remaining 21 items (13.1%). Seventeen of the 20 route section subscales, valence (positive/negative) scores, and overall scores (85.0%) demonstrated good/excellent reliability and 3 demonstrated moderate reliability. Of the 16 segment subscales, valence scores, and overall scores, 12 (75.0%) demonstrated good/excellent reliability, three demonstrated moderate reliability, and one demonstrated poor reliability. Of the 8 crossing subscales, valence scores, and overall scores, 6 (75.0%) demonstrated good/excellent reliability, and 2 demonstrated moderate reliability. The cul-de-sac subscale demonstrated good/excellent reliability.

Conclusions
MAPS items and subscales predominantly demonstrated moderate to excellent reliability. The subscales and scoring system represent a theoretically based framework for using these complex microscale data and may be applicable to other similar instruments.
Exposure to public natural space as a protective factor for emotional well-being among young people in Canada
Authors: Huynh Quynh , Craig Wendy , Janssen Ian , Pickett William 
Published: April 2013

AbstractBackgroundPositive emotional well-being is fundamentally important to general health status, and is linked to many favorable health outcomes. There is societal interest in understanding determinants of emotional well-being in adolescence, and the natural environment represents one potential determinant. Psychological and experimental research have each shown links between exposure to nature and both stress reduction and attention restoration. Some population studies have suggested positive effects of green space on various indicators of health. However, there are limited large-scale epidemiological studies assessing this relationship, specifically for populations of young people and in the Canadian context. The objective of this study was to examine the relationship between exposure to public natural space and positive emotional well-being among young adolescent Canadians.MethodsThis cross-sectional study was based upon the Canadian 2009/10 Health Behaviour in School-aged Children Survey with linked geographic information system (GIS) data. Following exclusions, the sample included 17 249 (grades 6 to 10, mostly ages 11 to 16) students from 317 schools. Features of the natural environment were extracted using GIS within a 5 km radius circular buffer surrounding each school. Multilevel logistic regression was used to examine the relationship between the presence of public natural space (features include green and blue spaces such as parks, wooded areas, and water bodies) and students’ reports of positive emotional well-being, while controlling for salient covariates and the clustered nature of the data.ResultsOver half of Canadian youth reported positive emotional well-being (58.5% among boys and 51.6% among girls). Relationships between measures of natural space and positive emotional well-being were weak and lacked consistency overall, but modest protective effects were observed in small cities. Positive emotional well-being was more strongly associated with other factors including demographic characteristics, family affluence, and perceptions of neighbourhood surroundings.ConclusionExposure to natural space in youth’s immediate living environment may not be a leading determinant of their emotional well-being. The relationship between natural space and positive emotional well-being may be context specific, and thus different for Canadian youth compared to adult populations and those studied in other nations. Factors of the individual context were stronger potential determinants.
Heart rate variability in sciatica patients referred to spine surgery: a case control study
Authors: Södervall Jarmo , Karppinen Jaro , Puolitaival Jukka , Kyllönen Eero , Kiviniemi Antti M , Tulppo Mikko P , Hautala Arto J 
Published: April 2013

AbstractBackgroundA chronic pain condition may result in altered autonomic nervous system regulation in various patient populations. We evaluated whether autonomic regulation differs between sciatica patients referred to spine surgery and age-matched healthy controls analyzed with heart rate variability techniques (HRV).MethodsHRV of patients (n = 201) and healthy controls (n = 138) were measured in standing conditions (5 min). High frequency (HF) power as an index of cardiac vagal modulation and the low-to-high-frequency (LF/HF) ratio and short-term fractal scaling exponent α1as indices of sympathovagal balance were analyzed. Pain intensity was assessed on a Visual Analog Scale (VAS) and perceived disability with Oswestry Disability Index.ResultsThe Oswestry and VAS scores were higher in the patients than in the controls (p < 0.0001 for both). HF power was markedly lower for the patients compared to the controls (p < 0.0001). The LF/HF ratio and α1were higher in the patients than in the controls (p < 0.01 for both). After adjusting for sex, smoking, BMI, and leisure-time physical activity, HF power (p = 0.011) and α1(p = 0.012) still differed between the groups. Among the patients, HF power was slightly associated with the duration of chronic pain (r = −.232, p = 0.003).ConclusionsSciatica patients referred to spine surgery had altered cardiac autonomic regulation expressed as decreased vagal activity and an increased sympathovagal balance toward sympathetic dominance when compared with age-matched healthy controls.
Herbal compound “Songyou Yin” attenuates hepatoma cell invasiveness and metastasis through downregulation of cytokines secreted by activated hepatic stellate cells
Authors: Jia Qing-An , Wang Zhi-Ming , Ren Zheng-Gang , Bu Yang , Xie Xiao-Ying , Wang Yan-Hong , Zhang Lan , Zhang Qiang-Bo , Xue Tong-Chun , Deng Li-Fen , Tang Zhao-You 
Published: April 2013

AbstractBackgroundActivated hepatic stellate cells (aHSCs) play an important role in the progression of hepatocellular carcinoma (HCC). Here, we determined if cytokines secreted in response to the herbal compound “Songyou Yin” (SYY) treatment of aHSCs could influence invasiveness and metastatic capabilities of hepatoma cells.MethodsPrimary rat hepatic stellate cells (HSCs) were isolated, activated, divided into SYY treated and untreated (nSYY) groups, and conditioned media (CM-SYY and CM-nSYY, respectively) were collected. The hepatoma cell line, McA-RH7777 was cultured for 4 weeks with SYY, CM-SYY, and CM-nSYY, designated McA-SYY, McA-SYYCM and McA-nSYYCM. The invasiveness and metastatic capabilities were evaluated using Matrigel invasion assayin vitroand pulmonary metastasisin vivo. Matrix metalloproteinase-2 (MMP-2), MMP-9, E-cadherin, N-cadherin, and vimentin protein levels in McA-SYYCM and McA-nSYYCM were evaluated by Western blot. Cytokine levels in conditioned media were tested using enzyme-linked immunosorbent assay (ELISA).ResultsMatrigel invasion assay indicated that the number of McA-SYYCM cells passing through the basement membrane was less than in McA-nSYYCM cells (P< 0.01). Similar results were also observedin vivofor lung metastasis. McA-SYYCM cells showed less pulmonary metastasis capabilities than McA-nSYYCM cells (P< 0.001). The reduced expression of MMP-2 and reversed epithelial to mesenchymal transition with E-cadherin upregulation, and N-cadherin and vimentin downregulation were also found in McA-SYYCM compared to McA-nSYYCM. Metastasis-promoting cytokines hepatocyte growth factor, interleukin-6, transforming growth factor-β1, and vascular endothelial growth factor were markedly decreased in CM-SYY compared to CM-nSYY.ConclusionsSYY attenuates hepatoma cell invasiveness and metastasis capabilities through downregulating cytokines secreted by activated hepatic stellate cells.
In vitro and in vivo antibacterial activities of cranberry press cake extracts alone or in combination with β-lactams against Staphylococcus aureus
Authors: Diarra Moussa S , Block Glenn , Rempel Heidi , Oomah B Dave , Harrison Judy , McCallum Jason , Boulanger Simon , Brouillette Éric , Gattuso Mariza , Malouin François 
Published: April 2013

Abstract

Background
Cranberry fruits possess many biological activities partly due to their various phenolic compounds; however the underlying modes of action are poorly understood. We studied the effect of cranberry fruit extracts on the gene expression of Staphylococcus aureus to identify specific cellular processes involved in the antibacterial action.

Methods
Transcriptional profiles of four S. aureus strains grown in broth supplemented or not with 2 mg/ml of a commercial cranberry preparation (Nutricran®90) were compared using DNA arrays to reveal gene modulations serving as markers for biological activity. Ethanol extracted pressed cakes from fresh fruits also produced various fractions and their effects on marker genes were demonstrated by qPCR. Minimal inhibitory concentrations (MICs) of the most effective cranberry fraction (FC111) were determined against multiple S. aureus strains and drug interactions with β-lactam antibiotics were also evaluated. Incorporation assays with [3H]-radiolabeled precursors were performed to evaluate the effect of FC111 on DNA, RNA, peptidoglycan (PG) and protein biosynthesis.

Results
Treatment of S. aureus with Nutricran®90 or FC111 revealed a transcriptional signature typical of PG-acting antibiotics (up-regulation of genes vraR/S, murZ, lytM, pbp2, sgtB, fmt). The effect of FC111 on PG was confirmed by the marked inhibition of incorporation of D-[3H]alanine. The combination of β-lactams and FC111 in checkerboard assays revealed a synergistic activity against S. aureus including strain MRSA COL, which showed a 512-fold drop of amoxicillin MIC in the presence of FC111 at MIC/8. Finally, a therapeutic proof of concept was established in a mouse mastitis model of infection. S. aureus-infected mammary glands were treated with amoxicillin, FC111 or a combination of both; only the combination significantly reduced bacterial counts from infected glands (P<0.05) compared to the untreated mice.

Conclusions
The cranberry fraction FC111 affects PG synthesis of S. aureus and acts in synergy with β-lactam antibiotics. Such a fraction easily obtained from poorly exploited press-cake residues, may find interesting applications in the agri-food sector and help reduce antibiotic usage in animal food production.