bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyaluronic Acid as Capacitation Inductor: Metabolic Changes and Membrane‐Associated Adenylate Cyclase Regulation
Authors: Fernández S , Córdoba M 
Published: September 2014

ContentsThe aim of this research was to study the effect of hyaluronic acid on bovine cryopreserved spermatozoa compared with heparin as regards the variation of capacitation induction, cellular oxidative metabolism and intracellular signal induced by membrane‐associated adenylate cyclase to propose hyaluronic acid as a capacitation inductor. Heparin or hyaluronic acid and lysophosphatidylcholine were used to induce sperm capacitation and acrosome reaction, respectively. 2′,5′‐dideoxyadenosine was used as a membrane‐associated adenylate cyclase inhibitor. The highest percentages of capacitated spermatozoa and live spermatozoa with acrosome integrity were obtained by incubating sperm for 60 min using 1000 μg/ml hyaluronic acid. In these conditions, capacitation induced by hyaluronic acid was lower compared with heparin; nonetheless both glycosaminoglycans promote intracellular changes that allow true acrosome reaction in vitro induced by lysophosphatidylcholine in bovine spermatozoa. Oxygen consumption in heparin‐capacitated spermatozoa was significantly higher than in hyaluronic acid‐treated spermatozoa. With all treatments, mitochondrial coupling was observed when a specific uncoupler of the respiratory chain was added. The inhibition of membrane‐associated adenylate cyclase significantly blocked capacitation induction produced by hyaluronic acid, maintaining a basal sperm oxygen uptake in contrast to heparin effect in which both sperm parameters were inhibited, suggesting that the membrane‐associated adenylate cyclase activation is involved in the intracellular signal mechanisms induced by both capacitation inductors, but only regulates mitochondrial oxidative phosphorylation in heparin‐capacitated spermatozoa.
Complexity of nursing care in acute care hospital patients: results of a pilot study with a newly developed questionnaire
Authors: Kleinknecht‐Dolf Michael , Grand Francis , Spichiger Elisabeth , Müller Marianne , Martin Jacqueline S. , Spirig Rebecca 
Published: September 2014

AimThe aim of this pilot study was to develop an instrument for measuring complexity of nursing care in hospitalised acute care patients as well as to examine its comprehensibility, its feasibility, the effort required for data collection, and its inter‐rater reliability as well as its face validity.MethodsThis pilot study was designed as a descriptive, explorative cross‐sectional survey with multiple measurements of the patient‐related complexity of nursing care and a supplemental qualitative questionnaire conducted on six units of a Swiss university hospital. The instrument to assess complexity of nursing care was developed on the framework of Perrow and encompasses on three subscales a total of 15 items with a 5‐point Likert scale.Ethical considerationsThe study was reviewed and approved by the Cantonal Ethics Committee.ResultsIn total, 866 assessments of complexity of nursing care were carried out on 234 patients. The variability of the results of the six units, from three different specialties, suggests that the sampling was suitable for capturing a wide spectrum of complexity. The results of the three subscales are consistent and the discussion of them with the participating units shows that they are also plausible. The verification of the inter‐rater reliability has satisfactory to high intersubjective correlation of the values. There were also a few suggestions for improving comprehensibility as well as on how to support user application. The time expenditure for the assessment between 2 to 5 minutes per patient was accurately.ConclusionWith the newly developed questionnaire to measure the complexity of nursing care in acute care hospitals it seems to be possible to assess and to quantify the complexity of nursing care in various acute care hospital settings. Based on the findings and the feedback of the participating users, the questionnaire needs to be improved for large‐scale application.
A Method of Positional Quality Control Testing for 2D and 3D Line Strings
Authors: Ariza‐López Francisco Javier , Rodríguez‐Avi José 
Published: September 2014

AbstractThis article presents a positional quality acceptance control method for 2D and 3D line strings based on a statistical hypothesis test. Two statistical models are applied together: a Binomial Model is applied over a Base Model. By means of the Base Model the method can be applied to any parametric or non‐parametric error model. The Base Model represents the hypothesis about the error behavior. The Binomial Model is fixed and consists of counting the number F of fail events in a sample of a determined size. The π parameter of the Binomial Model is derived from the Base Model by means of a desired tolerance. By comparing the probabilities associated to F and π a statistical acceptance/rejection decision is achieved. This method allows us to know and control the user's and producer's risk of acceptance/rejection. An example using a 2D line string data set from a commercial product is presented. The extension of the method to the 3D line string case is also presented. In order to facilitate the application of the method, some tables linking π with F and the control sample sizes are presented.
Measuring the Effectiveness of Mentoring as a Knowledge Translation Intervention for Implementing Empirical Evidence: A Systematic Review
Authors: Abdullah Ghadah , Rossy Dianne , Ploeg Jenny , Davies Barbara , Higuchi Kathryn , Sikora Lindsey , Stacey Dawn 
Published: September 2014

ABSTRACTBackgroundMentoring as a knowledge translation (KT) intervention uses social influence among healthcare professionals to increase use of evidence in clinical practice.AimTo determine the effectiveness of mentoring as a KT intervention designed to increase healthcare professionals’ use of evidence in clinical practice.MethodsA systematic review was conducted using electronic databases (i.e., MEDLINE, CINAHL), grey literature, and hand searching. Eligible studies evaluated mentoring of healthcare professionals responsible for patient care to enhance the uptake of evidence into practice. Mentoring is defined as (a) a mentor more experienced than mentee; (b) individualized support based on mentee's needs; and (c) involved in an interpersonal relationship as indicated by mutual benefit, engagement, and commitment. Two reviewers independently screened citations for eligibility, extracted data, and appraised quality of studies. Data were analyzed descriptively.ResultsOf 10,669 citations from 1988 to 2012, 10 studies were eligible. Mentoring as a KT intervention was evaluated in Canada, USA, and Australia. Exposure to mentoring compared to no mentoring improved some behavioral outcomes (one study). Compared to controls or other multifaceted interventions, multifaceted interventions with mentoring improved practitioners’ knowledge (four of five studies), beliefs (four of six studies), and impact on organizational outcomes (three of four studies). There were mixed findings for changes in professionals’ behaviors and impact on practitioners’ and patients’ outcomes: some outcomes improved, while others showed no difference.Linking Evidence to ActionOnly one study evaluated the effectiveness of mentoring alone as a KT intervention and showed improvement in some behavioral outcomes. The other nine studies that evaluated the effectiveness of mentoring as part of a multifaceted intervention showed mixed findings, making it difficult to determine the added effect of mentoring. Further research is needed to identify effective mentoring as a KT intervention.
Evaluation of the Carba NP Test for Carbapenemase Detection
Authors: Österblad Monica , Hakanen Antti J. , Jalava Jari 
Published: September 2014

ABSTRACT
The Carba NP test was evaluated against a panel of 61 carbapenemase-producing bacterial species (15 producing class A carbapenemases, 15 producing class D carbapenemases, and 31 producing metallo-β-lactamases) and against 111 isolates with non-wild-type carbapenem susceptibility but not producing carbapenemase. Carbapenemase production was verified by PCR and UV-spectrophotometric measurement of imipenem hydrolysis. No false positives were seen, but there were consistent problems with the detection of OXA-48-like enzymes and also some rarer class A enzymes.
Intra- and Extracellular Activities of Trimethoprim-Sulfamethoxazole against Susceptible and Multidrug-Resistant Mycobacterium tuberculosis
Authors: Davies Forsman L. , Schön T. , Simonsson U. S. H. , Bruchfeld J. , Larsson M. , Juréen P. , Sturegård E. , Giske C. G. , Ängeby K. 
Published: September 2014

ABSTRACT

We investigated the activity of trimethoprim-sulfamethoxazole (SXT) against
Mycobacterium tuberculosis
, the pathogen that causes tuberculosis (TB). The MIC distribution of SXT was 0.125/2.4 to 2/38 mg/liter for the 100 isolates tested, including multi- and extensively drug-resistant isolates (MDR/XDR-TB), whereas the intracellular MIC
90
of sulfamethoxazole (SMX) for the pansusceptible strain H37Rv was 76 mg/liter. In an exploratory analysis using a ratio of the unbound area under the concentration-time curve from 0 to 24 h over MIC (
f
AUC
0–24
/MIC) using ≥25 as a potential target, the cumulative fraction response was ≥90% at doses of ≥2,400 mg of SMX. SXT is a potential treatment option for MDR/XDR-TB.
A Novel High-Throughput Cell-Based Assay Aimed at Identifying Inhibitors of DNA Metabolism in Bacteria
Authors: Fan Jun , de Jonge Boudewijn L. M. , MacCormack Kathy , Sriram Shubha , McLaughlin Robert E. , Plant Helen , Preston Marian , Fleming Paul R. , Albert Robert , Foulk Melinda , Mills Scott D. 
Published: September 2014

ABSTRACT

Bacterial biosensor strains can be useful tools for the discovery and characterization of antibacterial compounds. A plasmid-based reporter vector containing a transcriptional fusion between the
recA
promoter and green fluorescence protein gene was introduced into an
Escherichia coli
Δ
tolC
strain to create a biosensor strain that selectively senses inhibitors of DNA metabolism via the SOS response. The strain was used to develop a high-throughput assay to identify new inhibitors of DNA metabolism. Screening of the AstraZeneca compound library with this strain identified known inhibitors of DNA metabolism, as well as novel chemotypes. The cellular target of one novel series was elucidated as DNA gyrase through genetic characterization of laboratory-generated resistant mutants followed by 50% inhibitory concentration measurements in a DNA gyrase activity assay. These studies validated the use of this antibiotic biosensor strain to identify novel selective inhibitors of DNA metabolism by high-throughput screening.
bla
NDM-5
Carried by an IncX3 Plasmid in Escherichia coli Sequence Type 167
Authors: Yang Ping , Xie Yi , Feng Ping , Zong Zhiyong 
Published: September 2014

ABSTRACT

bla
NDM-5
was found in
Escherichia coli
strain 0215 from a Chinese patient without travel history. Genomic sequencing and conjugation experiments were performed. Strain 0215 belonged to sequence type 167 (ST167) and had other resistance determinants, including
bla
TEM-135
,
bla
CTX-M-14
, and
aac
(
6
′)-
Ib. bla
NDM-5
was carried by a 47-kb self-transmissible IncX3 plasmid and was in a complex genetic context similar to that of
bla
NDM-1
on IncX3 plasmids. IncX3 plasmids might have emerged as a common vehicle mediating the spread of
bla
NDM
.
Pantothenate and Pantetheine Antagonize the Antitubercular Activity of Pyrazinamide
Authors: Dillon Nicholas A. , Peterson Nicholas D. , Rosen Brandon C. , Baughn Anthony D. 
Published: September 2014

ABSTRACT

Pyrazinamide (PZA) is a first-line tuberculosis drug that inhibits the growth of
Mycobacterium tuberculosis
via an as yet undefined mechanism. An
M. tuberculosis
laboratory strain that was auxotrophic for pantothenate was found to be insensitive to PZA and to the active form, pyrazinoic acid (POA). To determine whether this phenotype was strain or condition specific, the effect of pantothenate supplementation on PZA activity was assessed using prototrophic strains of
M. tuberculosis
. It was found that pantothenate and other β-alanine-containing metabolites abolished PZA and POA susceptibility, suggesting that POA might selectively target pantothenate synthesis. However, when the pantothenate-auxotrophic strain was cultivated using a subantagonistic concentration of pantetheine in lieu of pantothenate, susceptibility to PZA and POA was restored. In addition, we found that β-alanine could not antagonize PZA and POA activity against the pantothenate-auxotrophic strain, indicating that the antagonism is specific to pantothenate. Moreover, pantothenate-mediated antagonism was observed for structurally related compounds, including
n
-propyl pyrazinoate, 5-chloropyrazinamide, and nicotinamide, but not for nicotinic acid or isoniazid. Taken together, these data demonstrate that while pantothenate can interfere with the action of PZA, pantothenate synthesis is not directly targeted by PZA. Our findings suggest that targeting of pantothenate synthesis has the potential to enhance PZA efficacy and possibly to restore PZA susceptibility in isolates with
panD
-linked resistance.
Lactate Dehydrogenase Is the Key Enzyme for Pneumococcal Pyruvate Metabolism and Pneumococcal Survival in Blood
Authors: Gaspar Paula , Al-Bayati Firas A. Y. , Andrew Peter W. , Neves Ana Rute , Yesilkaya Hasan 
Published: September 2014

ABSTRACT

Streptococcus pneumoniae
is a fermentative microorganism and causes serious diseases in humans, including otitis media, bacteremia, meningitis, and pneumonia. However, the mechanisms enabling pneumococcal survival in the host and causing disease in different tissues are incompletely understood. The available evidence indicates a strong link between the central metabolism and pneumococcal virulence. To further our knowledge on pneumococcal virulence, we investigated the role of lactate dehydrogenase (LDH), which converts pyruvate to lactate and is an essential enzyme for redox balance, in the pneumococcal central metabolism and virulence using an isogenic
ldh
mutant. Loss of LDH led to a dramatic reduction of the growth rate, pinpointing the key role of this enzyme in fermentative metabolism. The pattern of end products was altered, and lactate production was totally blocked. The fermentation profile was confirmed by
in vivo
nuclear magnetic resonance (NMR) measurements of glucose metabolism in nongrowing cell suspensions of the
ldh
mutant. In this strain, a bottleneck in the fermentative steps is evident from the accumulation of pyruvate, revealing LDH as the most efficient enzyme in pyruvate conversion. An increase in ethanol production was also observed, indicating that in the absence of LDH the redox balance is maintained through alcohol dehydrogenase activity. We also found that the absence of LDH renders the pneumococci avirulent after intravenous infection and leads to a significant reduction in virulence in a model of pneumonia that develops after intranasal infection, likely due to a decrease in energy generation and virulence gene expression.
Human Antibodies to PhtD, PcpA, and Ply Reduce Adherence to Human Lung Epithelial Cells and Murine Nasopharyngeal Colonization by Streptococcus pneumoniae
Authors: Kaur Ravinder , Surendran Naveen , Ochs Martina , Pichichero Michael E. 
Published: September 2014

ABSTRACT

Streptococcus pneumoniae
adherence to human epithelial cells (HECs) is the first step in pathogenesis leading to infections. We sought to determine the role of human antibodies against
S. pneumoniae
protein vaccine candidates PhtD, PcpA, and Ply in preventing adherence to lung HECs
in vitro
and mouse nasopharyngeal (NP) colonization
in vivo
. Human anti-PhtD, -PcpA, and -Ply antibodies were purified and Fab fragments generated. Fabs were used to test inhibition of adherence of TIGR4 and nonencapsulated strain RX1 to A549 lung HECs. The roles of individual proteins in adherence were tested using isogenic mutants of strain TIGR4. Anti-PhtD, -PcpA, and -Ply human antibodies were assessed for their ability to inhibit NP colonization
in vivo
by passive transfer of human antibody in a murine model. Human antibodies generated against PhtD and PcpA caused a decrease in adherence to A549 cells (
P
< 0.05). Anti-PhtD but not anti-PcpA antibodies showed a protective role against mouse NP colonization. To our surprise, anti-Ply antibodies also caused a significant (
P
< 0.05) reduction in
S. pneumoniae
colonization. Our results support the potential of PhtD, PcpA, and Ply protein vaccine candidates as alternatives to conjugate vaccines to prevent non-serotype-specific
S. pneumoniae
colonization and invasive infection.
Antibodies to Staphylococcus aureus Serotype 8 Capsular Polysaccharide React with and Protect against Serotype 5 and 8 Isolates
Authors: Park Saeyoung , Gerber Sabina , Lee Jean C. 
Published: September 2014

ABSTRACT

Most
Staphylococcus aureus
isolates produce either a serotype 5 (CP5) or 8 (CP8) capsular polysaccharide, and the CP antigens are targets for vaccine development. Since CP5 and CP8 have similar trisaccharide repeating units, it is important to identify an epitope shared by both CP5 and CP8. To characterize cross-reactivity between CP5 and CP8, the immunogenicity of CP5 and CP8 conjugate vaccines in mice and rabbits was evaluated by serological assays. Immune sera were also tested for functional activity by
in vitro
opsonophagocytic-killing assays and a murine bacteremia model. Antibodies to the CP5-cross-reactive material 197 (CRM197) conjugate vaccine bound only to purified CP5. In contrast, antibodies to the CP8-CRM conjugate vaccine reacted with CP8 and (to a lesser extent) CP5. De-O-acetylation of CP5 increased its reactivity with CP8 antibodies. Moreover, CP8 antibodies bound to
Pseudomonas aeruginosa
O11 lipopolysaccharide, which has a trisaccharide repeating unit similar to that of the
S. aureus
CPs. CP8-CRM antibodies mediated
in vitro
opsonophagocytic killing of
S. aureus
expressing CP5 or CP8, whereas CP5-CRM antibodies were serotype specific. Passive immunization with antiserum to CP5-CRM or CP8-CRM protected mice against bacteremia induced by a serotype 5
S. aureus
isolate, suggesting that CP8-CRM elicits antibodies cross-reactive to CP5. The identification of epitopes shared by CP5 and CP8 may inform the rational design of a vaccine to protect against infections caused by CP5- or CP8-producing strains of
S. aureus
.
Toll-Like Receptor-Triggered Calcium Mobilization Protects Mice against Bacterial Infection through Extracellular ATP Release
Authors: Ren Hua , Teng Yunfei , Tan Binghe , Zhang Xiaoyu , Jiang Wei , Liu Mingyao , Jiang Wenzheng , Du Bing , Qian Min 
Published: September 2014

ABSTRACT

Extracellular ATP (eATP), released as a “danger signal” by injured or stressed cells, plays an important role in the regulation of immune responses, but the relationship between ATP release and innate immune responses is still uncertain. In this study, we demonstrated that ATP was released through Toll-like receptor (TLR)-associated signaling in both
Escherichia coli
-infected mice and lipopolysaccharide (LPS)- or Pam3CSK4-treated macrophages. This ATP release could be blocked completely only by
N
-ethylmaleimide (NEM), not by carbenoxolone (CBX), flufenamic acid (FFA), or probenecid, suggesting the key role of exocytosis in this process. Furthermore, LPS-induced ATP release could also be reduced dramatically through suppressing calcium mobilization by use of U73122, caffeine, and thapsigargin (TG). In addition, the secretion of interleukin-1β (IL-1β) and CCL-2 was enhanced significantly by ATP, in a time- and dose-dependent manner. Meanwhile, macrophage-mediated phagocytosis of bacteria was also promoted significantly by ATP stimulation. Furthermore, extracellular ATP reduced the number of invading bacteria and protected mice from peritonitis by activating purinergic receptors. Mechanistically, phosphorylation of AKT and ERK was overtly increased by ATP in antibacterial immune responses. Accordingly, if we blocked the P2X- and P2Y-associated signaling pathway by using suramin and pyridoxal phosphate-6-azo(benzene-2,4-disulfonic acid), tetrasodium salt (PPADS), the ATP-enhanced immune response was restrained significantly. Taken together, our findings reveal an internal relationship between danger signals and TLR signaling in innate immune responses, which suggests a potential therapeutic significance of calcium mobilization-mediated ATP release in infectious diseases.
Epigenetic Inactivation and Tumor-Suppressor Behavior of NGFR in Human Colorectal Cancer
Authors: Yang Zuli , Chen Hao , Huo Lijun , Yang Zihuan , Bai Yang , Fan Xinjuan , Ni Beibei , Fang Lekun , Hu Jun , Peng Junsheng , Wang Lei , Wang Jianping 
Published: September 2014

Abstract
The nerve growth factor receptor (NGFR/p75) is a potential tumor suppressor, but its role in colorectal cancer is unknown. Here, the hypermethylation status, biologic function, and clinical relevance were determined for p75NGFR in colorectal cancer. The methylation status and expression of p75NGFR were assessed in colorectal cancer cell lines and clinical tissues by bisulfite genomic sequencing (BGS), qRT-PCR, and immunoblot assay. Methylation of p75NGFR was frequently found in colorectal cancer, leading to its silencing or downregulation, and it was effectively restored by a demethylation agent. The overexpression of p75NGFR in multiple colorectal cancer cell model systems significantly inhibited cell proliferation (concomitant with G1-phase arrest), invasion, and colony formation and induced cell apoptosis. In contrast, p75NGFR knockdown significantly promoted proliferative and invasive phenotypes. Importantly, p75NGFR methylation was observed in the majority of primary colorectal cancer specimens and was associated with histologic grade and preoperative serum CA19-9 levels. Multivariate analysis indicated that patients who lack p75NGFR have reduced overall survival (64% vs. 75%, P = 0.028) and disease-free survival (61% vs. 72%, P = 0.034) compared with p75NGFR-positive patients. In conclusion, p75NGFR is predominantly silenced or downregulated in colorectal cancer, and its biologic activities are consistent with it being a relevant tumor suppressor.
Implications: p75NGFR is a candidate tumor suppressor and has independent prognostic potential in colorectal cancer. Mol Cancer Res; 13(1); 107–19. ©2014 AACR.