743 research outputs found
Comparison of Plankton Catch by Three Light-Trap Designs in the Northern Gulf of Mexico
The ichthyoplankton catch and zooplankton biomass estimates of three light-trap designs-cylindrical, quatrefoil, and rectangular-were compared over three consecutive nights at an offshore petroleum platform in the northern Gulf of Mexico. The quatrefoil light trap had higher fish and zooplankton abundance estimates than the other two designs. Categorical analysis of the two abundant fish taxa, Opisthonema oglinum and Anchoa spp., indicated that catch by the quatrefoil and rectangular traps was similar, capturing more larvae than juveniles and more O. oglinum than Anchoa spp. relative to cylindrical trap catch. Across all fish species, the quatrefoil captured a greater percentage of larvae. Other ontogenetic and species-specific differences were noted among the light-trap designs. Samples from vertical plankton tows underestimated larger size classes compared to light-trap catch. Light-trap catch per unit effort (CPUE) declined through the night, especially for the quatrefoil, and increased with depth. In contrast, the percentage of larvae captured across all traps increased through the night and decreased with depth, indicating that CPUE was related mostly to juvenile catch. The percentage of larvae also decreased with increasing water current speed
Hard-wired epimysial recordings from normal and reinnervated muscle using a bone-anchored device
Background: A combined approach for prosthetic attachment and control using
a transcutaneous bone-anchored device and implanted muscle electrodes can improve function for upper-limb amputees. The bone-anchor provides a transcutaneous feed-through for muscle signal recording. This approach can be combined
with targeted muscle reinnervation (TMR) to further improve myoelectric control.
Methods: A bone-anchored device was implanted trans-tibially in n = 8 sheep with
a bipolar recording electrode secured epimysially to the peroneus tertius muscle.
TMR was carried out in a single animal: the peroneus tertius was deinnervated and
the distal portion of the transected nerve to the peroneus muscle was coapted to
a transected nerve branch previously supplying the tibialis anterior muscle. For
12 weeks (TMR) or 19 weeks (standard procedure), epimysial muscle signals were
recorded while animals walked at 2 km·h−1.
Results: After 19 weeks implantation following standard procedure, epimysial recording signal-to-noise ratio (SNR) was 18.7 dB (± 6.4 dB, 95% CI) with typical
recordings falling in the range 10–25 dB. Recoveries in gait and muscle signals
were coincident 6 weeks post-TMR; initial muscle activity was identifiable 3 weeks
post-TMR though with low signal amplitude and signal-to-noise ratio compared
with normal muscle recordings.
Conclusions: Following recovery, muscle signals were recorded reliably over 19 weeks
following implantation. In this study, targeted reinnervation was successful in parallel with bone-anchor implantation, with recovery identified 6 weeks after surger
Acute dental infections managed in an outpatient parenteral antibiotic program setting: prospective analysis and public health implications
BACKGROUND: The number of Acute Dental Infections (ADI) presenting for emergency department (ED) care are steadily increasing. Outpatient Parenteral Antibiotic Therapy (OPAT) programs are increasingly utilized as an alternative cost-effective approach to the management of serious infectious diseases but their role in the management of severe ADI is not established. This study aims to address this knowledge gap through evaluation of ADI referrals to a regional OPAT program in a large Canadian center. METHODS: All adult ED and OPAT program ADI referrals from four acute care adult hospitals in Calgary, Alberta, were quantified using ICD diagnosis codes in a regional reporting system. Citywide OPAT program referrals were prospectively enrolled over a five-month period from February to June 2014. Participants completed a questionnaire and OPAT medical records were reviewed upon completion of care. RESULTS: Of 704 adults presenting to acute care facilities with dental infections during the study period 343 (49%) were referred to OPAT for ADI treatment and 110 were included in the study. Participant mean age was 44 years, 55% were women, and a majority of participants had dental insurance (65%), had seen a dentist in the past six months (65%) and reported prior dental infections (77%), 36% reporting the current ADI as a recurrence. Median length of parenteral antibiotic therapy was 3 days, average total course of antibiotics was 15-days, with a cumulative 1326 antibiotic days over the study period. There was no difference in total duration of antibiotics between broad and narrow spectrum regimes. Conservative cost estimate of OPAT care was 597,434 (83%) compared with hospitalization. CONCLUSIONS: ADI represent a common preventable cause of recurrent morbidity. Although OPAT programs may offer short-term cost savings compared with hospitalization, risks associated with extended antibiotic exposures and delayed definitive dental management must also be gauged. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12879-017-2303-2) contains supplementary material, which is available to authorized users
Early Cenozoic denudation of central west Britain in response to transient and permanent uplift above a mantle plume
Upwelling mantle plumes beneath continental crust are predicted to produce difficult to quantify, modest uplift and denudation. The contribution of permanent and transient components to the uplift is also difficult to distinguish. A pulse of denudation in Britain in the Early Paleogene has been linked, although with some controversy, with the arrival of the proto-Iceland mantle plume. In this contribution we show that combining apatite and zircon (U-Th-Sm)/He and apatite fission track analyses from central west Britain with numerical modeling clearly identifies a pulse of early Cenozoic denudation. The data indicate that rock uplift and denudation were centered on the northern East Irish Sea Basin and 1.0–2.4 km of rocks were removed during the latest Cretaceous-early Paleogene. Uplift and erosion appears to have started a few million years before the earliest magmatism in the region. The regional denudation pattern mirrors the distribution of low-density magmatic rocks that has been imaged in the deep crust. However, the injection of the underplating melt is not enough to account for the total denudation. An additional regional uplift of at least 300 m is required, which is consistent with a transient thermal effect from the hot mantle plume. The rapid exhumation event ceased by ~40 Ma and the data do not require significant Neogene exhumation
The OSCE in a pre-registration osteopathy program: Introduction and psychometric properties
Objective
To investigate the psychometric properties of the objective structured clinical examination (OSCE) conducted in the final year of a pre-professional osteopathy program. A variety of metrics are used to determine the reliability and validity of the examination.
Methods
Data from the OSCE conducted in 2011 was collated and analysed to establish the pass/fail rates, cost of the examination, internal consistency, and variance components. The examination was conducted over two days with students completing 5 stations on day 1 and 4 stations on day 2. Each station was of 15 min duration and there were 2 examiners per station.
Results
Forty-eight students and 31 examiners were involved in the examination. Twenty-six students failed at least one station with six students failing three or more stations. Cronbach's alpha was greater than 0.80 for all stations indicating that each is internally consistent and over 50% of the variance in the students' total score for a station was due to the students themselves. The total cost of conducting the examination was $AUD12,933.20.
Conclusion
The results of the study suggest that the OSCE format is an appropriate method for assessing clinical competency in osteopathic education. The OSCE should be used in conjunction with other forms of assessment to develop and overall picture of the students' clinical competency. Some modifications to the format of the assessment are required to improve the examination and these will be the subject of further studies
PTPN2, a Candidate Gene for Type 1 Diabetes, Modulates Interferon-γ–Induced Pancreatic β-Cell Apoptosis
OBJECTIVE:
The pathogenesis of type 1 diabetes has a strong genetic component. Genome-wide association scans recently identified novel susceptibility genes including the phosphatases PTPN22 and PTPN2. We hypothesized that PTPN2 plays a direct role in beta-cell demise and assessed PTPN2 expression in human islets and rat primary and clonal beta-cells, besides evaluating its role in cytokine-induced signaling and beta-cell apoptosis.
RESEARCH DESIGN AND METHODS:
PTPN2 mRNA and protein expression was evaluated by real-time PCR and Western blot. Small interfering (si)RNAs were used to inhibit the expression of PTPN2 and downstream STAT1 in beta-cells, allowing the assessment of cell death after cytokine treatment.
RESULTS:
PTPN2 mRNA and protein are expressed in human islets and rat beta-cells and upregulated by cytokines. Transfection with PTPN2 siRNAs inhibited basal- and cytokine-induced PTPN2 expression in rat beta-cells and dispersed human islets cells. Decreased PTPN2 expression exacerbated interleukin (IL)-1beta + interferon (IFN)-gamma-induced beta-cell apoptosis and turned IFN-gamma alone into a proapoptotic signal. Inhibition of PTPN2 amplified IFN-gamma-induced STAT1 phosphorylation, whereas double knockdown of both PTPN2 and STAT1 protected beta-cells against cytokine-induced apoptosis, suggesting that STAT1 hyperactivation is responsible for the aggravation of cytokine-induced beta-cell death in PTPN2-deficient cells.
CONCLUSIONS:
We identified a functional role for the type 1 diabetes candidate gene PTPN2 in modulating IFN-gamma signal transduction at the beta-cell level. PTPN2 regulates cytokine-induced apoptosis and may thereby contribute to the pathogenesis of type 1 diabetes
Arthritis prevention in the pre-clinical phase of RA with abatacept (the APIPPRA study): a multi-centre, randomised, double-blind, parallel-group, placebo-controlled clinical trial protocol.
TRIAL DESIGN: We present a study protocol for a multi-centre, randomised, double-blind, parallel-group, placebo-controlled trial that seeks to test the feasibility, acceptability and effectiveness of a 52-week period of treatment with the first-in-class co-stimulatory blocker abatacept for preventing or delaying the onset of inflammatory arthritis. METHODS: The study aimed to recruit 206 male or female subjects from the secondary care hospital setting across the UK and the Netherlands. Participants who were at least 18 years old, who reported inflammatory sounding joint pain (clinically suspicious arthralgia) and who were found to be positive for serum autoantibodies associated with rheumatoid arthritis (RA) were eligible for enrolment. All study subjects were randomly assigned to receive weekly injections of investigational medicinal product, either abatacept or placebo treatment over the course of a 52-week period. Participants were followed up for a further 52 weeks. The primary endpoint was defined as the time to development of at least three swollen joints or to the fulfilment of the 2010 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification criteria for RA using swollen but not tender joints, whichever endpoint was met first. In either case, swollen joints were confirmed by ultrasonography. Participants, care givers, and those assessing the outcomes were all blinded to group assignment. Clinical assessors and ultrasonographers were also blinded to each other's assessments for the duration of the study. CONCLUSIONS: There is limited experience of the design and implementation of trials for the prevention of inflammatory joint diseases. We discuss the rationale behind choice and duration of treatment and the challenges associated with defining the "at risk" state and offer pragmatic solutions in the protocol to enrolling subjects at risk of RA. TRIAL REGISTRATION: Current Controlled Trials, ID: ISRCTN46017566 . Registered on 4 July 2014
Long-range DNA looping and gene expression analyses identify DEXI as an autoimmune disease candidate gene
The chromosome 16p13 region has been associated with several autoimmune diseases, including type 1 diabetes (T1D) and multiple sclerosis (MS). CLEC16A has been reported as the most likely candidate gene in the region, since it contains the most disease-associated single-nucleotide polymorphisms (SNPs), as well as an imunoreceptor tyrosine-based activation motif. However, here we report that intron 19 of CLEC16A, containing the most autoimmune disease-associated SNPs, appears to behave as a regulatory sequence, affecting the expression of a neighbouring gene, DEXI. The CLEC16A alleles that are protective from T1D and MS are associated with increased expression of DEXI, and no other genes in the region, in two independent monocyte gene expression data sets. Critically, using chromosome conformation capture (3C), we identified physical proximity between the DEXI promoter region and intron 19 of CLEC16A, separated by a loop of >150 kb. In reciprocal experiments, a 20 kb fragment of intron 19 of CLEC16A, containing SNPs associated with T1D and MS, as well as with DEXI expression, interacted with the promotor region of DEXI but not with candidate DNA fragments containing other potential causal genes in the region, including CLEC16A. Intron 19 of CLEC16A is highly enriched for transcription-factor-binding events and markers associated with enhancer activity. Taken together, these data indicate that although the causal variants in the 16p13 region lie within CLEC16A, DEXI is an unappreciated autoimmune disease candidate gene, and illustrate the power of the 3C approach in progressing from genome-wide association studies results to candidate causal genes
Television viewing in Thai infants and toddlers: impacts to language development and parental perceptions
<p>Abstract</p> <p>Background</p> <p>Effects of television to language development in infants and toddlers, especially in the Asian children, are inconclusive. This study aimed to (a) study time spent on television in Thai infants and toddlers (age < 2 years), (b) investigate the association between time spent on television (as recommended by the American Academy of Paediatrics (AAP), < 2 hours per day) and language development in Thai 2-year-old children, and (c) explore parental perceptions on television toward their child's development.</p> <p>Methods</p> <p>Two hundred and sixty children and their parents were recruited into the study. Time spent on television and parental perceptions on television viewing toward their child's development were recorded during face-to-face and telephone interviews. Language development was assessed at the age of 2 years using the Clinical Linguistic Auditory Milestone Scale (CLAMS), and parents' report. Association between delayed language development and time spent on television viewing, as well as other various parameters such as gender, maternal education and family income, were analysed using a multivariate logistic regression model.</p> <p>Results</p> <p>Most Thai infants and toddlers watched television at the age of 6 months, 1 year and 2 years old (98.0, 95.3 and 96.7%, respectively). On average, 1-year-old children watched television 1.23 ± 1.42 hours per day. This increased to 1.69 ± 1.56 hours per day when they were 2 years old. However, watching television longer than 2 hours per day did not associate with delayed language development. On multivariate logistic regression analysis, gender (male) was the only significant factor associated with delayed language development (OR = 6.9, 95% CI = 1.5–31.3). Moreover, 75%, 71%, and 66% of Thai parents believed that television viewing yielded benefits to children's developments.</p> <p>Conclusion</p> <p>Thai children commenced watching television at an early age and the amount of television viewing time increased by age. Most parents had positive perceptions to television viewing. The study found no association between time spent on television viewing (≥ 2 hours per day) and delayed language development at the age of 2 years.</p> <p>Gender (male) was the only variable associated with delayed language development.</p
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