232 research outputs found
Comparison of surgical stress index (SSI)-guided analgesia and standard clinical practice during routine general anaesthesia : a pilot study
It is well-known that excessive intraoperative stress (nociceptive stimulus) results in various physiological changes, such as immunological, haemodynamic or endocrine ‘stress response’, which thereby may compromise patients’ outcome, influence the length of hospital stay and overall costs of hospital care. To achieve an appropriate balance of nociception – anti-nociception during general anaesthesia is very important and necessary.
Achieving an appropriate balance of nociception – anti-nociception during general anaesthesia depends on an indicator which can assess accurately the balance of nociception – anti-nociception to guide analgesic delivery. Surgical stress index (SSI) has been proven to have a better performance in assessing the balance of nociception – anti-nociception during general anaesthesia compared with more traditional variables like blood pressure and heart rate.
We designed a prospective, randomized, controlled clinical study, which included two groups – SSI-guided analgesia group and standard analgesia practice group, to investigate the effect of SSI-guided analgesia on recovery time, anaesthetics consumption, incidence of unwanted events during general anaesthesia with propofol and remifentanil during a constant hypnotic level.
The results demonstrated that SSI-guided analgesia resulted in a significant reduction of remifentail consumption, less incidence of unwanted events (hypertension, hypotension, tachycardia and movement) and in a similar recovery time during general anaesthesia when compared with the standard analgesia practice protocol.
Our study also further proved that SSI has a better performance in detecting the balance of nociception – anti-nociception than state entropy (SE), response entropy (RE), difference between response entropy and state entropy (RE-SE), blood pressure and heart rate during general anaesthesia.
However, the ‘ideal’ range of SSI for guiding analgesia needs to be further investigated
Partially Metal-Coated Tips for Near-Field Nanospectroscopy
Scanning probes with functional optical responses are key components of scanning near-field optical microscopes. For nanospectroscopy performed at IR and terahertz (THz) frequencies, one major challenge is that the commonly used metal-coated silicon tips yield nonadjustable coupling efficiency across the spectrum, which greatly limits the signal-to-noise ratio. Here, we test the possibility of a generic design scheme for wavelength-selective tip enhancement via finite-element numerical modeling. We employ a Si-based tip with various gold-coating lengths on the top, yielding a customizable near-field field strength at the tip apex. Calculations show a wavelength-dependent enhancement factor of the metal-coated tip due to the geometrical antenna resonances, which can be precisely tuned throughout a broad spectral range from visible to terahertz frequencies by adjusting the length of the metal coating. By changing the coating pattern into a chiral helical structure on an achiral tip, we also demonstrate the usefulness of coating-length effect in designing high-performance enantiomeric near-field scanning. Our methods and findings offer interesting perspectives for developing near-field optical probes, pushing the detection and resolution limits of tip-enhanced near-field detections, such as fluorescence, Raman, IR, and THz nanospectroscopies
De novo transcriptome analysis of the sandworm (Sipunculus nudus) and identification of differentially expressed genes associated with body size
The sandworm (Sipunculus nudus) is an aquatic species of economic importance because of its high nutritional and medicinal value. Under the same culture conditions, substantial individual growth variation is often found in populations of sandworms. However, the genetic mechanisms of individual growth variation are poorly understood. In this study, the transcriptome of the body wall muscle of the sandworm at different growth rates was analyzed by Illumina sequencing and bioinformatics analysis. A total of 185 181 unigenes were obtained after processing raw reads and about 96,824 (47.72%) of them were annotated. Among the annotated transcripts, 418 differentially expressed genes were identified, of which 207 were upregulated and 211 were downregulated in large worms relative to small worms. We identified several genes that had a possible association with individual growth variation. These results will provide insight into the growth mechanism of sandworm, and will further assist in the selective breeding of improved strains of this species
Plasma lensing interpretation of FRB 20201124A bursts at the end of September 2021
When the radio photons propagate through a non-uniform electron density
volume, the plasma lensing effect can induce an extreme magnification to the
observed flux at certain frequencies. Because the plasma lens acts as a
diverging lens, it can extremely suppress the observed flux when aligned with
source. These two properties can theoretically cause a highly magnified Fast
Radio Burst (FRB) to faint or even disappear for a period of time. In this
paper, we interpret that the significant increase in burst counts followed by a
sudden quenching in FRB 20201124A in September 2021 can be attributed to plasma
lensing. Based on the one-dimensional Gaussian lens model, we search for double
main-peak structures in spectra just before its extinction on September 29,
2021. After the de-dispersion and de-scintillation procedures, we find eight
bursts with double main-peaks at stable positions. There are three parameters
in our modelling, the height and width of the one-dimension Gaussian lens and
its distance to the source. We reformulate them as a combined parameter
. The frequency spectra can give an
accurate estimation of corresponding to , while the time of
arrival only give a relatively loose constraint on .
Comparing with the observation dynamic spectra, we suggest that for a plasma
lens in host galaxy, e.g., , the width of
lens can not be larger than . At last, we estimate the relative
transverse motion velocity between the lens and source,
.Comment: 9 pages, 12 figures. Comments are welcom
Decreased adiponectin and increased inflammation expression in epicardial adipose tissue in coronary artery disease
<p>Abstract</p> <p>Background</p> <p>Disorders of endocrine substances in epicardial adipose tissue are known causes of coronary artery disease (CAD). Adiponectin is associated with cardiovascular disease. However, expression of adiponectin in epicardial adipose tissue and its function in CAD pathogenesis is unclear. This study investigates adiponectin expression in epicardial adipose tissue in CAD patients.</p> <p>Methods</p> <p>Vessels or adipose tissue samples collected from CAD patients and non-CAD controls were examined after immunochemical staining. Adiponectin, cytokines of interleukin-6 (IL-6) and necrosis factor-α (TNF-α) and toll-like receptor 4 (TLR4) expression level in adipose tissue were measured using real-time quantitative RT-PCR. Adiponectin concentrations in peripheral and coronary sinus vein plasma were measured with enzyme-linked immunosorbent assay. Peripheral vein plasma biochemistries were performed with routine laboratory techniques. Monocytes were collected from blood using lymphocyte separation medium. Expression level of cytokines and transcription factor NF-κB were measured to learn the effect of adiponectin on stearic acid-stimulated monocytes. Percentage of TLR4 positive monocytes was analyzed using flow cytometry.</p> <p>Results</p> <p>Histological examination revealed increased macrophage infiltration into epicardial adipose tissue of CAD patients. Decreased adiponectin displayed by real-time quantitative RT-PCR was associated with enhanced cytokines of IL-6 and TNF-α or TLR4 expression level in epicardial adipose tissue, suggesting decreased circulating adiponectin may be useful as a more sensitive predictor for coronary atherosclerosis than routine laboratory examinations. Adiponectin suppressed secretion of IL-6 and TNF-α in stimulated monocytes and TLR4 was expressed on cell surfaces.</p> <p>Conclusions</p> <p>Endocrine disorders in epicardial adipose tissue are strongly linked to CAD, and adiponectin has a protective effect by inhibiting macrophage-mediated inflammation.</p
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