96 research outputs found
Personalized Genomic Medicine and the Rhetoric of Empowerment
Advocates of “personalized” genomic medicine maintain that it is revolutionary not just in what it can reveal to us, but in how it will enable us to take control of our health. But we should not assume that patient empowerment always yields positive outcomes. To assess the social impact of personalized medicine, we must anticipate how the virtue might go awry in practice
Daily Heart Rate Variability before and after Concussion in an American College Football Player
This case report demonstrates the effects of sport-related concussion (SRC) on heart rate variability (HRV) in an American college football player. Daily measures of resting, ultra-short natural logarithm of the root mean square of successive differences (LnRMSSD), subjective wellbeing, and Player Load were obtained each training day throughout a 4-week spring camp and 4 weeks of preseason training. SRC occurred within the first 2 weeks of the preseason. During spring camp and preseason pre-SRC, the athlete demonstrated minimal day-to-day fluctuations in LnRMSSD, which increased post-SRC (LnRMSSD coefficient of variation pre-SRC ≤ 3.1%, post-SRC = 5.8%). Moderate decrements in daily-averaged LnRMSSD were observed post-SRC relative to pre-SRC (Effect Size ± 90% Confidence Interval = −1.12 ± 0.80), and the 7-day rolling average fell below the smallest worthwhile change for the remainder of the preseason. LnRMSSD responses to SRC appeared similar to trends associated with stress and training fatigue. Therefore, performance and sports medicine staff should maintain regular communication regarding player injury and fatigue status so that HRV can be interpreted in the appropriate context. Detection and monitoring of autonomic dysregulation post-SRC may require near-daily assessment, as LnRMSSD showed greater daily fluctuations rather than chronic suppression following the head injury
Methods of Attaching or Grafting Carbon Nanotubes to Silicon Surfaces and Composite Structures Derived Therefrom
The present invention is directed toward methods of attaching or grafting carbon nanotubes (CNTs) to silicon surfaces. In some embodiments, such attaching or grafting occurs via functional groups on either or both of the CNTs and silicon surface. In some embodiments, the methods of the present invention include: (1) reacting a silicon surface with a functionalizing agent (such as oligo(phenylene ethynylene)) to form a functionalized silicon surface; (2) dispersing a quantity of CNTs in a solvent to form dispersed CNTs; and (3) reacting the functionalized silicon surface with the dispersed CNTs. The present invention is also directed to the novel compositions produced by such methods
Relationships between Workload, Heart Rate Variability, and Performance in a Recreational Endurance Runner
[EN] Background: The association between heart rate variability (HRV), training load (TL),
and performance is poorly understood. Methods: A middle-aged recreational female runner was
monitored during a competitive 20-wk macrocycle divided into first (M1) and second mesocycle
(M2) in which best performances over 10 km and 21 km were recorded. Volume (km), session rating
of perceived exertion (sRPE), TL, and monotony (mean TL/SD TL) were the workload parameters
recorded. The root mean square of the successive differences in R-R intervals (RMSSD), its coefficient
of variation (RMSSDcv), and the RMSSD:RR ratio were the HRV parameters monitored. Results:
During M2, RMSSD (p = 0.006) and RMSSD:RR (p = 0.002) were significantly increased, while RR
was significantly reduced (p = 0.017). Significant correlations were identified between monotony
and volume (r = 0.552; p = 0.012), RR (r = 0.447; p = 0.048), and RMSSD:RR (r = −0.458; p = 0.042).
A sudden reduction in RMSSD (from 40.31 to 24.34 ms) was observed the day before the first
symptoms of an influenza. Conclusions: The current results confirm the practicality of concurrent
HRV and sRPE monitoring in recreational runners, with the RMSSD:RR ratio indicative of specific
adaptations. Excessive training volume may be associated to both elevated monotony and reduced
RMSSD:RR. Identification of mesocycle patterns is recommended for better individualization of the
periodization use
Use of Functionalized Carbon Nanotubes for Covalent Attachment of Nanotubes to Silicon
The purpose of the invention is to covalently attach functionalized carbon nanotubes to silicon. This step allows for the introduction of carbon nanotubes onto all manner of silicon surfaces, and thereby introduction of carbon nano - tubes covalently into silicon-based devices, onto silicon particles, and onto silicon surfaces. Single-walled carbon nanotubes (SWNTs) dispersed as individuals in surfactant were functionalized. The nano - tube was first treated with 4-t-butylbenzenediazonium tetrafluoroborate to give increased solubility to the carbon nanotube; the second group attached to the sidewall of the nanotube has a silyl-protected terminal alkyne that is de-protected in situ. This gives a soluble carbon nanotube that has functional groups appended to the sidewall that can be attached covalently to silicon. This reaction was monitored by UV/vis/NJR to assure direct covalent functionalization
A linear RFQ ion trap for the Enriched Xenon Observatory
The design, construction, and performance of a linear radio-frequency ion
trap (RFQ) intended for use in the Enriched Xenon Observatory (EXO) are
described. EXO aims to detect the neutrinoless double-beta decay of Xe
to Ba. To suppress possible backgrounds EXO will complement the
measurement of decay energy and, to some extent, topology of candidate events
in a Xe filled detector with the identification of the daughter nucleus
(Ba). The ion trap described here is capable of accepting, cooling, and
confining individual Ba ions extracted from the site of the candidate
double-beta decay event. A single trapped ion can then be identified, with a
large signal-to-noise ratio, via laser spectroscopy.Comment: 18 pages, pdflatex, submitted to NIM
Esculentin-2CHa-Related Peptides Modulate Islet Cell Function and Improve Glucose Tolerance in Mice with Diet-Induced Obesity and Insulin Resistance
The frog skin host-defense peptide esculentin-2CHa (GFSSIFRGVA10KFASKGLGK
D20LAKLGVDLVA30CKISKQC) displays antimicrobial, antitumor, and immunomodulatory
properties. This study investigated the antidiabetic actions of the peptide and selected analogues.
Esculentin-2CHa stimulated insulin secretion from rat BRIN-BD11 clonal pancreatic
β-cells at concentrations greater than 0.3 nM without cytotoxicity by a mechanism involving
membrane depolarization and increase of intracellular Ca2+. Insulinotropic activity was
attenuated by activation of KATP channels, inhibition of voltage-dependent Ca2+ channels
and chelation of extracellular Ca2+. The [L21K], [L24K], [D20K, D27K] and [C31S,C37S]
analogues were more potent but less effective than esculentin-2CHa whereas the [L28K]
and [C31K] analogues were both more potent and produced a significantly (P < 0.001)
greater maximum response. Acute administration of [L28K]esculentin-2CHa (75 nmol/kg
body weight) to high fat fed mice with obesity and insulin resistance enhanced glucose tolerance
and insulin secretion. Twice-daily administration of this dose of [L28K]esculentin-
2CHa for 28 days had no significant effect on body weight, food intake, indirect calorimetry
or body composition. However, mice exhibited decreased non-fasting plasma glucose
(P < 0.05), increased non-fasting plasma insulin (P < 0.05) as well as improved glucose tolerance
and insulin secretion (P < 0.01) following both oral and intraperitoneal glucose
loads. Impaired responses of isolated islets from high fat fed mice to established insulin
secretagogues were restored by [L28K]esculentin-2CHa treatment. Peptide treatment was
accompanied by significantly lower plasma and pancreatic glucagon levels and normalization
of α-cell mass. Circulating triglyceride concentrations were decreased but plasma cholesterol
and LDL concentrations were not significantly affected. The data encourage further
investigation of the potential of esculentin-2CHa related peptides for treatment of patients
with type 2 diabetes
Type 1 diabetes patients increase CXCR4+ and CXCR7+ haematopoietic and endothelial progenitor cells with exercise, but the response is attenuated
Background: Exercise mobilizes angiogenic cells, which stimulate vascular repair. However, limited research suggests exercise-induced increase of endothelial progenitor cell (EPCs) is completely lacking in type 1 diabetes (T1D). Clarification, along with investigating how T1D influences exercise-induced increases of other angiogenic cells (hematopoietic progenitor cells; HPCs) and cell surface expression of chemokine receptor 4 (CXCR4) and 7 (CXCR7), is needed. Methods: Thirty T1D patients and 30 matched non-diabetes controls completed 45 minutes of incline walking. Circulating HPCs (CD34+ , CD34+ CD45dim) and EPCs (CD34+ VEGFR2+ , CD34+CD45dimVEGFR2+ ), and subsequent expression of CXCR4 and CXCR7, were enumerated by flow cytometry at rest and post-exercise. Results: Counts of HPCs, EPCs and expression of CXCR4 and CXCR7 were significantly lower at rest in the T1D group. In both groups, exercise increased circulating angiogenic cells. However, increases was largely attenuated in the T1D group, up to 55% lower, with CD34+ (331±437 Δcells/mL vs 734±876 Δcells/mL p=0.048), CD34+VEGFR2+ (171±342 Δcells/mL vs 303±267 Δcells/mL, p=0.006) and CD34+ VEGFR2+CXCR4+ (126±242 Δcells/mL vs 218±217 Δcells/mL, p=0.040) significantly lower. Conclusion: Exercise-induced increases of angiogenic cells is possible in T1D patients, albeit attenuated compared to controls. Decreased mobilization likely results in reduced migration to, and repair of, vascular damage, potentially limiting the cardiovascular benefits of exercise. Trial registration: ISRCTN6373920
The discovery, distribution and diversity of DNA viruses associated with Drosophila melanogaster in Europe
International audienceDrosophila melanogaster is an important model for antiviral immunity in arthropods, but very few DNA viruses have been described from the family Drosophilidae. This deficiency limits our opportunity to use natural host-pathogen combinations in experimental studies, and may bias our understanding of the Drosophila virome. Here we report fourteen DNA viruses detected in a metagenomic analysis of approximately 6500 pool-sequenced Drosophila, sampled from 47 European locations between 2014 and 2016. These include three new nudiviruses, a new and divergent entomopoxvirus, a virus related to Leptopilina boulardi filamentous virus, and a virus related to Musca domestica salivary gland hypertrophy virus. We also find an endogenous genomic copy of galbut virus, a dsRNA partitivirus, segregating at very low frequency. Remarkably, we find that Drosophila Vesanto virus, a small DNA virus previously described as a bidnavirus, may be composed of up to 12 segments and thus represent a new lineage of segmented DNA viruses. Two of the DNA viruses, Drosophila Kallithea nudivirus and Drosophila Vesanto virus are relatively common, found in 2% or more of wild flies. The others are rare, with many likely to be represented by a single infected fly. We find that virus prevalence in Europe reflects the prevalence seen in publicly-available datasets, with Drosophila Kallithea nudivirus and Drosophila Vesanto virus the only ones commonly detectable in public data from wild-caught flies and large population cages, and the other viruses being rare or absent. These analyses suggest that DNA viruses are at lower prevalence than RNA viruses in D. melanogaster, and may be less likely to persist in laboratory cultures. Our findings go some way to redressing an earlier bias toward RNA virus studies in Drosophila, and lay the foundation needed to harness the power of Drosophila as a model system for the study of DNA viruses
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