bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of a New Chromogenic Agar Medium for Detection of Shiga Toxin-Producing Escherichia coli (STEC) and Relative Prevalences of O157 and Non-O157 STEC in Manitoba, Canada
Authors: Wylie J. L. , Van Caeseele P. , Gilmour M. W. , Sitter D. , Guttek C. , Giercke S. 
Published: November 2012

ABSTRACT

This study assesses the detection performance of CHROMagar STEC medium relative to a reference cytotoxin assay and describes the current relative prevalence of O157 and non-O157 Shiga toxin-producing
Escherichia coli
(STEC) serotypes within the province of Manitoba, Canada. Over a 10-month period, 205 nonfrozen routine stool submissions to Cadham Provincial Laboratory (CPL) were used to assess the performance of CHROMagar STEC. Of the 205 stools, 14 were identified as true positives by a cytotoxin assay, with resultant CHROMagar STEC sensitivity, specificity, and positive predictive and negative predictive values of 85.7%, 95.8%, 60.0%, and 98.9%, respectively. Using a separate panel of 111 STEC strains, CHROMagar STEC was shown to support the growth of 96 (86.5%) isolates. To assess relative prevalence, attempts were made to isolate by any means all STEC strains identified at CPL over a 17-month period. Of 49 isolates (representing 86.0% of all STEC infections detected), only 28.6% were O157 STEC strains. Of the 35 non-O157 STEC strains, 29 were subjected to further molecular analysis. In contrast to earlier results from our area, carriage of
stx
2
appears to have increased. Overall, although CHROMagar STEC is not recommended as a primary screen, our results indicate that it is an effective supplemental medium for the isolation of probable STEC strains. Increased isolation of these serotypes is warranted to better understand their prevalence, clinical characteristics, and epidemiology and aid in the development or enhancement of food safety control programs targeting all STEC serotypes.
Detection of Heterogeneity of Borrelia burgdorferi in Ixodes Ticks by Culture-Dependent and Culture-Independent Methods
Authors: Xu Guang , Wesker Jaime , White Caitlin , Campbell Jason , Reich Nicholas G. , Rich Stephen M. 
Published: November 2012

ABSTRACT

Abilities to detect heterogeneity of
ospC
genotypes of the Lyme disease spirochete
Borrelia burgdorferi
in the tick vector by
in vitro
culture (IVC) and direct PCR (dPCR) were compared. IVC failed to detect one-third of the
ospC
genotypes detected by dPCR. Among IVC results, common
ospC
genotypes were overrepresented while occurrence of rare genotypes was underestimated.
Antigenicity and Immunogenicity of RV144 Vaccine AIDSVAX Clade E Envelope Immunogen Is Enhanced by a gp120 N-Terminal Deletion
Authors: Alam S. Munir , Liao Hua-Xin , Tomaras Georgia D. , Bonsignori Mattia , Tsao Chun-Yen , Hwang Kwan-Ki , Chen Haiyan , Lloyd Krissey E. , Bowman Cindy , Sutherland Laura , Jeffries Thomas L. , Kozink Daniel M. , Stewart Shelley , Anasti Kara , Jaeger Frederick H. , Parks Robert , Yates Nicole L. , Overman R. Glenn , Sinangil Faruk , Berman Phillip W. , Pitisuttithum Punnee , Kaewkungwal Jaranit , Nitayaphan Sorachai , Karasavva Nicos , Rerks-Ngarm Supachai , Kim Jerome H. , Michael Nelson L. , Zolla-Pazner Susan , Santra Sampa , Letvin Norman L. , Harrison Stephen C. , Haynes Barton F. 
Published: November 2012

ABSTRACTAn immune correlates analysis of the RV144 HIV-1 vaccine trial revealed that antibody responses to the gp120 V1/V2 region correlated inversely with infection risk. The RV144 protein immunogens (A244-rp120 and MN-rgp120) were modified by an N-terminal 11-amino-acid deletion (Δ11) and addition of a herpes simplex virus (HSV) gD protein-derived tag (gD). We investigated the effects of these modifications on gp120 expression, antigenicity, and immunogenicity by comparing unmodified A244 gp120 with both Δ11 deletion and gD tag and with Δ11 only. Analysis of A244 gp120, with or without Δ11 or gD, demonstrated that the Δ11 deletion, without the addition of gD, was sufficient for enhanced antigenicity to gp120 C1 region, conformational V2, and V1/V2 gp120 conformational epitopes. RV144 vaccinee serum IgGs bound more avidly to A244 gp120 Δ11 than to the unmodified gp120, and their binding was blocked by C1, V2, and V1/V2 antibodies. Rhesus macaques immunized with the three different forms of A244 gp120 proteins gave similar levels of gp120 antibody titers, although higher antibody titers developed earlier in A244 Δ11 gp120-immunized animals. Conformational V1/V2 monoclonal antibodies (MAbs) gave significantly higher levels of blocking of plasma IgG from A244 Δ11 gp120-immunized animals than IgG from animals immunized with unmodified A244 gp120, thus indicating a qualitative difference in the V1/V2 antibodies induced by A244 Δ11 gp120. These results demonstrate that deletion of N-terminal residues in the RV144 A244 gp120 immunogen improves both envelope antigenicity and immunogenicity.
High-Risk Human Papillomavirus E6 Oncoproteins Interact with 14-3-3ζ in a PDZ Binding Motif-Dependent Manner
Authors: Boon Siaw Shi , Banks Lawrence 
Published: November 2012

ABSTRACT

Cervical cancer develops through the combined activities of the human papillomavirus (HPV) E6 and E7 oncoproteins. A defining characteristic of E6 oncoproteins derived from cancer-causing HPV types is the presence of a PDZ binding motif (PBM) at the extreme carboxy terminus of the protein which is absent from E6 proteins derived from the so-called low-risk HPV types. Within this PBM is also a protein kinase A (PKA) phospho-acceptor site, which is thought to negatively regulate the association of E6 with its PDZ domain-containing substrates. We can now show that phosphorylation of E6 by PKA and/or AKT confers the ability to interact with 14-3-3ζ. The interaction is direct and specific for the high-risk HPV E6 oncoproteins, although there are significant differences in the efficiencies with which HPV-16, HPV-18, and HPV-31 E6 oncoproteins can associate with 14-3-3ζ; this correlates directly with their respective susceptibilities to phosphorylation by PKA and/or AKT. We demonstrate here that the interaction between E6 and 14-3-3ζ also requires integrity of the E6 PBM, and downregulation of 14-3-3ζ results in a marked reduction in the levels of HPV-18 E6 expression in HeLa cells. Using phospho-specific anti-E6 antibodies, we also demonstrate significant levels of E6 phosphorylation
in vivo
. These studies redefine the potential relevance of the E6 PBM in the development of cervical cancer, suggesting that interaction with 14-3-3ζ, as well as the more well-established interactions with PDZ domain-containing substrates, is likely to be responsible for the biological activities attributed to this region of the high-risk HPV E6 oncoproteins.
Inhibition of Cellular Autophagy Deranges Dengue Virion Maturation
Authors: Mateo Roberto , Nagamine Claude M. , Spagnolo Jeannie , Méndez Ernesto , Rahe Michael , Gale Michael , Yuan Junying , Kirkegaard Karla 
Published: November 2012

ABSTRACT

Autophagy is an important component of the innate immune response, directly destroying many intracellular pathogens. However, some pathogens, including several RNA viruses, subvert the autophagy pathway, or components of the pathway, to facilitate their replication. In the present study, the effect of inhibiting autophagy on the growth of dengue virus was tested using a novel inhibitor, spautin-1 (
s
pecific and
p
otent
aut
ophagy
in
hibitor 1). Inhibition of autophagy by spautin-1 generated heat-sensitive, noninfectious dengue virus particles, revealing a large effect of components of the autophagy pathway on viral maturation. A smaller effect on viral RNA accumulation was also observed. Conversely, stimulation of autophagy resulted in increased viral titers and pathogenicity in the mouse. We conclude that the presence of functional autophagy components facilitates viral RNA replication and, more importantly, is required for infectious dengue virus production. Pharmacological inhibition of host processes is an attractive antiviral strategy to avoid selection of treatment-resistant variants, and inhibitors of autophagy may prove to be valuable therapeutics against dengue virus infection and pathogenesis.
Nuclear Export Signal-Interacting Protein Forms Complexes with Lamin A/C-Nups To Mediate the CRM1-Independent Nuclear Export of Large Hepatitis Delta Antigen
Authors: Huang Cheng , Jiang Jia-Yin , Chang Shin C. , Tsay Yeou-Guang , Chen Mei-Ru , Chang Ming-Fu 
Published: November 2012

ABSTRACT
Nuclear export is an important process that not only regulates the functions of cellular factors but also facilitates the assembly of viral nucleoprotein complexes. Chromosome region maintenance 1 (CRM1) that mediates the transport of proteins bearing the classical leucine-rich nuclear export signal (NES) is the best-characterized nuclear export receptor. Recently, several CRM1-independent nuclear export pathways were also identified. The nuclear export of the large form of hepatitis delta antigen (HDAg-L), a nucleocapsid protein of hepatitis delta virus (HDV), which contains a CRM1-independent proline-rich NES, is mediated by the host NES-interacting protein (NESI). The mechanism of the NESI protein in mediating nuclear export is still unknown. In this study, NESI was characterized as a highly glycosylated membrane protein. It interacted and colocalized well in the nuclear envelope with lamin A/C and nucleoporins. Importantly, HDAg-L could be coimmunoprecipitated with lamin A/C and nucleoporins. In addition, binding of the cargo HDAg-L to the C terminus of NESI was detected for the wild-type protein but not for the nuclear export-defective HDAg-L carrying a P205A mutation [HDAg-L(P205A)]. Knockdown of lamin A/C effectively reduced the nuclear export of HDAg-L and the assembly of HDV. These data indicate that by forming complexes with lamin A/C and nucleoporins, NESI facilitates the CRM1-independent nuclear export of HDAg-L.
Proteolytic Processing of the Human Immunodeficiency Virus Envelope Glycoprotein Precursor Decreases Conformational Flexibility
Authors: Haim Hillel , Salas Ignacio , Sodroski Joseph 
Published: November 2012

ABSTRACT
The mature envelope glycoprotein (Env) spike on the surface of human immunodeficiency virus type 1 (HIV-1) virions is derived by proteolytic cleavage of a trimeric gp160 glycoprotein precursor. Remarkably, proteolytic processing of the HIV-1 Env precursor results in changes in Env antigenicity that resemble those associated with glutaraldehyde fixation. Apparently, proteolytic processing of the HIV-1 Env precursor decreases conformational flexibility of the Env trimeric complex, differentially affecting the integrity/accessibility of epitopes for neutralizing and nonneutralizing antibodies.
Effects of enzyme replacement therapy in adult patients with Fabry disease on cardiac structure and function: a retrospective cohort study of the Fabry Münster Study (FaMüS) data
Authors: Engelen Markus A , Brand Eva , Baumeister Timo B , Marquardt T , Duning Thomas , Osada Nani , Schaefer Roland M , Stypmann Joerg 
Published: November 2012

ObjectiveFabry disease (FD) is an X-linked inborn error of glycosphingolipid catabolism caused by deficient lysosomal α-galactosidase A activity. Progressive accumulation of globotriaosylceramide and related glycosphingolipids in vascular endothelial lysosomes of the heart, kidneys and brain is responsible for the main disease manifestations. The aim of our study was to assess short-term and long-term effects of enzyme replacement therapy (ERT) on cardiac mass and function.DesignRetrospective cohort study.SettingHospital outpatient clinic.Participants40 FD patients (21 men, 19 women) receiving agalsidase β-ERT.Outcome measuresThe focus at baseline and follow-up examinations was on structural, functional (Doppler-echocardiography) as well as electrical changes (ECG) and blood pressure.ResultsIn the Early Group, systolic and diastolic blood pressures significantly decreased. Left-ventricular (LV) also decreased; however, wall thickness and LV mass index showed no further increase. VE as an indicator for diastolic function significantly improved (64±21 vs 75±27 cm/s, p=0.038). There were no significant changes of ECG parameters. There were few relevant changes in the Late Group, albeit systolic blood pressure significantly decreased and QRS duration significantly increased. In conclusion, echocardiographic left-ventricular mass index, interventricular septum thickness, left-ventricular posterior wall, left-ventricular end-diastolic dimension) and diastolic function parameters are valuable for follow-up and guidance of therapy.ConclusionsThe primary positive impact of ERT appears to be an early effect after the start of therapy, and early initiation of ERT should be recommended.
Missed opportunities: childhood learning disabilities as early indicators of risk among homeless adults with mental illness in Vancouver, British Columbia
Authors: Patterson Michelle Louise , Moniruzzaman Akm , Frankish Charles James , Somers Julian M 
Published: November 2012

ObjectivesIt is well documented that early-learning problems and poor academic achievement adversely impact child development and a wide range of adult outcomes; however, these indicators have received scant attention among homeless adults. This study examines self-reported learning disabilities (LD) in childhood as predictors of duration of homelessness, mental and substance use disorders, physical health, and service utilisation in a sample of homeless adults with current mental illness.DesignThis study was conducted using the baseline sample from a randomised controlled trial (RCT).SettingParticipants were sampled from the community in Vancouver, British Columbia.ParticipantsThe total sample included 497 adult participants who met criteria for absolute homelessness or precarious housing and a current mental disorder based on a structured diagnostic interview. Learning disabilities in childhood were assessed by asking adult participants whether they thought they had an LD in childhood and if anyone had told them they had an LD. Only participants who responded positively to both questions (n=133) were included in the analyses.Outcome measuresPrimary outcomes include current mental disorders, substance use disorders, physical health, service utilisation and duration of homelessness.ResultsIn multivariable regression models, self-reported LD during childhood independently predicted self-reported educational attainment and lifetime duration of homelessness as well as a range of mental health, physical health and substance use problems, but did not predict reported health or justice service utilisation.ConclusionsChildhood learning problems are overrepresented among homeless adults with complex comorbidities and long histories of homelessness. Our findings are consistent with a growing body of literature indicating that adverse childhood events are potent risk factors for a number of adult health and psychiatric problems, including substance abuse.Trials registration numberThis trial has been registered with the International Standard Randomised Control Trial Number Register and assignedISRCTN42520374.
Serum leptin is not correlated with body fat in severe food restriction
Authors: Gairdner Sarah E. , Amara Catherine E. 
Published: November 2012

Leptin is an adipose-derived hormone with established roles in energy balance that can impact the response to refeeding after malnutrition. Although the amount of circulating leptin has traditionally been associated with the amount of adipose tissue, controversy exists as to whether this relationship is constant in both humans and animals and over a wide range of body composition. Our objective was to evaluate whether the leptin – body fat ratio is constant in the range of healthy to low body mass in female Wistar rats. Eight ad libitum fed (C) and eight food-restricted (FR) rats were compared over a period of four weeks. FR rats attained the target 75% of baseline body mass after the first two weeks, which was maintained for the remaining two weeks. Serum leptin and IGF-1 (ELISA) and body composition (DXA) were measured at baseline (t0) and once weekly for the remainder of the study (t1–t4). The leptin – body fat ratio was reduced during the two-week period of weight loss (t0 = 0.036 ± 0.016 (ng·mL–1)·g–1 vs. t1 = 0.010 ± 0.004 (ng·mL–1)·g–1 and t2 = 0.015 ± 0.007 (ng·mL–1)·g–1, p < 0.05). Leptin concentration plateaued at its nadir (~0.24 (ng·mL–1)·g–1) at fat mass < 22 g. IGF-1 was correlated with lean mass (r = 0.45, p < 0.05) and fat mass (r = 0.58, p < 0.05), regardless of body mass. We concluded that the leptin – body fat ratio was reduced early in food restriction and the correlation between these two variables was absent at low body fat.
Effects of prior short multiple-sprint exercises with different intersprint recoveries on the slow component of oxygen uptake during high-intensity exercise
Authors: Lanzi Stefano , Borrani Fabio , Wolf Martin , Gojanovic Boris , Malatesta Davide 
Published: November 2012

This study compares the effects of two short multiple-sprint exercise (MSE) (6 × 6 s) sessions with two different recovery durations (30 s or 180 s) on the slow component of oxygen uptake ([Formula: see text]O2) during subsequent high-intensity exercise. Ten male subjects performed a 6-min cycling test at 50% of the difference between the gas exchange threshold and [Formula: see text]O2peak (Δ50). Then, the subjects performed two MSEs of 6 × 6 s separated by two intersprint recoveries of 30 s (MSE30) and 180 s (MSE180), followed 10 min later by the Δ50 (Δ5030 and Δ50180, respectively). Electromyography (EMG) activities of the vastus medialis and lateralis were measured throughout each exercise bout. During MSE30, muscle activity (root mean square) increased significantly (p ≤ 0.04), with a significant leftward-shifted median frequency of the power density spectrum (MDF; p ≤ 0.01), whereas MDF was significantly rightward-shifted during MSE180 (p = 0.02). The mean [Formula: see text]O2 value was significantly higher in MSE30 than in MSE180 (p < 0.001). During Δ5030, [Formula: see text]O2 and the deoxygenated hemoglobin ([HHb]) slow components were significantly reduced (–27%, p = 0.02, and –34%, p = 0.003, respectively) compared with Δ50. There were no significant modifications of the [Formula: see text]O2 slow component in Δ50180 compared with Δ50 (p = 0.32). The neuromuscular and metabolic adaptations during MSE30 (preferential activation of type I muscle fibers evidenced by decreased MDF and a greater aerobic metabolism contribution to the required energy demands), but not during MSE180, may lead to reduced [Formula: see text]O2 and [HHb] slow components, suggesting an alteration in motor units recruitment profile (i.e., change in the type of muscle fibers recruited) and (or) an improved muscle O2 delivery during subsequent exercise.
Effects of swim training on liver carcinogenesis in male Wistar rats fed a low-fat or high-fat diet
Authors: Aguiar e Silva Marco Aurélio , Vechetti-Junior Ivan José , Nascimento André Ferreira do , Furtado Kelly Silva , Azevedo Luciana , Ribeiro Daniel Araki , Barbisan Luis Fernando 
Published: November 2012

The present study aimed to investigate the beneficial effects of swim training on the promotion–progression stages of rat liver carcinogenesis. Male Wistar rats were submitted to chemically induced liver carcinogenesis and allocated into 4 major groups, according their dietary regimen (16 weeks) and swim training of 5 days per week (8 weeks): 2 groups were fed low-fat diet (LFD, 6% fat) and trained or not trained and 2 groups were fed high-fat diet (HFD, 21% fat) and trained or not trained. At week 20, the animals were killed and liver samples were processed for histological analyses; immunohistochemical detection of persistent or remodeling preneoplastic lesions (pPNL and rPNL) expressing placental glutathione S-transferase (GST-P) enzyme; or proliferating cell nuclear antigen (PCNA), cleaved caspase-3, and bcl-2 protein levels by Western blotting or malonaldehyde (MDA) and total glutathione detection by HPLC. Overall analysis indicated that swim training reduced the body weight and body fat in both LFD and HFD groups, normalized total cholesterol levels in the HFD group while decreased the MDA levels, increased glutathione levels and both number of GST-P-positive pPNL and hepatocellular adenomas in LFD group. Also, a favorable balance in PCNA, cleaved caspase-3, and bcl-2 levels was detected in the liver from the LFD-trained group in relation to LFD-untrained group. The findings of this study indicate that the swim training protocol as a result of exercise postconditioning may attenuate liver carcinogenesis under an adequate dietary regimen with lowered fat intake.
Changes in body weight, composition, and shape: a 4-year study of college students
Authors: Gropper Sareen S. , Simmons Karla P. , Connell Lenda Jo , Ulrich Pamela V. 
Published: November 2012

The objectives of this study were to examine changes in body weight, body mass index (BMI), body composition, and shape in a group of male and female students over the 4-year college period. Anthropometric assessments including height and weight (via standard techniques), body composition (via bioelectrical impedance analysis), and body shape (via 3-dimensional body scanning) were conducted at the beginning of the freshman year and end of the senior year in 131 college students. Four-year changes included significant (p < 0.0001) gains in weight (3.0 kg), BMI (1.0 kg·m–2), body fat (3.6%), and absolute fat mass (3.2 kg). Males gained significantly (p < 0.0001) greater amounts of weight, BMI, percent and absolute fat mass, and fat-free mass than females. Weight change ranged from –8.7 to +16.8 kg. About 70% of the participants gained weight, which averaged 5.3 kg; significant (p < 0.0001) gains in BMI, fat-free mass, absolute fat mass, and percent body fat and significant (p < 0.0005) increases in neck, chest–bust, waist, hips, seat, and biceps circumferences were also observed in this weight gain group. The percentage of participants classified as overweight–obese increased from 18% to 31%. The number of females and males with ≥30% and 20% body fat, respectively, increased from n = 14 to n = 26 (with n = 4 exhibiting normal weight obesity) over the 4-year period. The waist circumference changes were significantly (p < 0.0001) correlated with both weight and percent body fat changes. In conclusion, the increasing prevalence of obesity and normal weight obesity among this college population suggests the need for additional health promotion strategies on college campuses.