Perioperative use of dexmedetomidine is associated with reduction in postoperative analgesic requirements. This study examined whether dexmedetomidine added to i.v. patient-controlled analgesia (PCA) ...morphine could improve analgesia while reducing opioid-related side-effects.
In this double-blinded, randomized, controlled study, 100 women undergoing abdominal total hysterectomy were allocated to receive either morphine 1 mg ml−1 alone (Group M) or morphine 1 mg ml−1 plus dexmedetomidine 5 μg ml−1 (Group D) for postoperative i.v. PCA, which was programmed to deliver 1 ml per demand with a 5 min lockout interval and no background infusion. Cumulative PCA requirements, pain intensities, cardiovascular and respiratory variables, and PCA-related adverse events were recorded for 24 h after operation.
Compared with Group M, patients in Group D required 29% less morphine during the 0–24 h postoperative period and reported significantly lower pain levels from the second postoperative hour onwards and throughout the study. Whereas levels of sedation were similar between the groups at each observational time point, decreases in heart rate and mean blood pressure from presurgery baseline at 1, 2, and 4 h after operation were significantly greater in Group D (by a range of 5–7 beats min−1 and 10–13%, respectively). The 4–24 h incidence of nausea was significantly lower in Group D (34% vs 56.3%, P<0.05). There was no bradycardia, hypotension, oversedation, or respiratory depression.
The addition of dexmedetomidine to i.v. PCA morphine resulted in superior analgesia, significant morphine sparing, less morphine-induced nausea, and was devoid of additional sedation and untoward haemodynamic changes.
The 3D printed bulk samples fabricated by selective laser melting (SLM) of the additive manufacturing technique are usually considered to be 3D isotropic in microstructures and mechanical responses. ...This study systematically investigates the anisotropic responses in terms of hardness and electrochemical resistance for the X-, Y- and Z-planes of the SLM Ti-6Al-4V bulk samples fabricated with the zigzag laser path strategy. Results show that all SLM planes exhibit no significant difference in Young's modulus compared to the mechanically rolled plate. However, the X-plane, referred to the cross-sectional plane perpendicular to the laser moving direction, is found ~20% lower hardness and the lowest corrosion resistance compared to the Y- and Z-planes. The underlying reasoning is researched and discussed. The microstructure observations indicate that artifact holes are induced in the X-plane due to un-uniform laser intensity distribution between two neighboring printing lines. Alternatively, the Y- and Z-planes exhibit dense morphology due to multiple heating while zigzag scanning. Experimental results also indicate that the SLM materials exhibit higher corrosion resistance than the commercial rolled materials.
The optical design and performance of the recently opened 13A biological small‐angle X‐ray scattering (SAXS) beamline at the 3.0 GeV Taiwan Photon Source of the National Synchrotron Radiation ...Research Center are reported. The beamline is designed for studies of biological structures and kinetics in a wide range of length and time scales, from angstrom to micrometre and from microsecond to minutes. A 4 m IU24 undulator of the beamline provides high‐flux X‐rays in the energy range 4.0–23.0 keV. MoB4C double‐multilayer and Si(111) double‐crystal monochromators (DMM/DCM) are combined on the same rotating platform for a smooth rotation transition from a high‐flux beam of ∼4 × 1014 photons s−1 to a high‐energy‐resolution beam of ΔE/E ≃ 1.5 × 10−4; both modes share a constant beam exit. With a set of Kirkpatrick–Baez (KB) mirrors, the X‐ray beam is focused to the farthest SAXS detector position, 52 m from the source. A downstream four‐bounce crystal collimator, comprising two sets of Si(311) double crystals arranged in a dispersive configuration, optionally collimate the DCM (vertically diffracted) beam in the horizontal direction for ultra‐SAXS with a minimum scattering vector q down to 0.0004 Å−1, which allows resolving ordered d‐spacing up to 1 µm. A microbeam, of 10–50 µm beam size, is tailored by a combined set of high‐heat‐load slits followed by micrometre‐precision slits situated at the front‐end 15.5 m position. The second set of KB mirrors then focus the beam to the 40 m sample position, with a demagnification ratio of ∼1.5. A detecting system comprising two in‐vacuum X‐ray pixel detectors is installed to perform synchronized small‐ and wide‐angle X‐ray scattering data collections. The observed beamline performance proves the feasibility of having compound features of high flux, microbeam and ultra‐SAXS in one beamline.
The optical design and performance of the BioSAXS beamline at the Taiwan Photon Source are reported
Virtual photons can mediate interaction between atoms, resulting in an energy shift known as a collective Lamb shift. Observing the collective Lamb shift is challenging, since it can be obscured by ...radiative decay and direct atom-atom interactions. Here, we place two superconducting qubits in a transmission line terminated by a mirror, which suppresses decay. We measure a collective Lamb shift reaching 0.8% of the qubit transition frequency and twice the transition linewidth. We also show that the qubits can interact via the transmission line even if one of them does not decay into it.
Amelogenesis imperfecta (AI) is a diverse group of inherited diseases featured by various presentations of enamel malformations that are caused by disturbances at different stages of enamel ...formation. While hypoplastic AI suggests a thickness defect of enamel resulting from aberrations during the secretory stage of amelogenesis, hypomaturation AI indicates a deficiency of enamel mineralization and hardness established at the maturation stage. Mutations in ENAM, which encodes the largest enamel matrix protein, enamelin, have been demonstrated to cause generalized or local hypoplastic AI. Here, we characterized 2 AI families with disparate hypoplastic and hypomaturation enamel defects and identified 2 distinct indel mutations at the same location of ENAM, c588+1del and c.588+1dup. Minigene splicing assays demonstrated that they caused frameshifts and truncation of ENAM proteins, p.Asn197Ilefs*81 and p.Asn197Glufs*25, respectively. In situ hybridization of Enam on mouse mandibular incisors confirmed its restricted expression in secretory stage ameloblasts and suggested an indirect pathogenic mechanism underlying hypomaturation AI. In silico analyses indicated that these 2 truncated ENAMs might form amyloid structures and cause protein aggregation with themselves and with wild-type protein through the added aberrant region at their C-termini. Consistently, protein secretion assays demonstrated that the truncated proteins cannot be properly secreted and impede secretion of wild-type ENAM. Moreover, compared to the wild-type, overexpression of the mutant proteins significantly increased endoplasmic reticulum stress and upregulated the expression of unfolded protein response (UPR)–related genes and TNFRSF10B, a UPR-controlled proapoptotic gene. Caspase, terminal deoxynucleotidyl transferase UTP nick-end labeling (TUNEL), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assays further revealed that both truncated proteins, especially p.Asn197Ilefs*81, induced cell apoptosis and decreased cell survival, suggesting that the 2 ENAM mutations cause AI through ameloblast cell pathology and death rather than through a simple loss of function. This study demonstrates that an ENAM mutation can lead to generalized hypomaturation enamel defects and suggests proteinopathy as a potential pathogenesis for ENAM-associated AI.
Summary
Background
The risk factors for gastrointestinal bleeding (GIB) in clopidogrel users have not been identified.
Aim
To clarify whether clopidogrel use is a risk factor for upper GIB (UGIB) and ...lower GIB (LGIB) and identify the risk factors in clopidogrel users.
Methods
Using the National Health Insurance Research Database of Taiwan, 3238 clopidogrel users and 12 952 age‐, sex‐, and enrolment time‐matched controls in a 1:4 ratio were extracted for comparison from a cohort dataset of 1 000 000 randomly sampled subjects. Cox proportional hazard regression models were used to identify the independent risk factors for UGIB and LGIB in all enrollees and clopidogrel users after adjustments for age, gender, comorbidity i.e., coronary artery disease, hypertension, diabetes, chronic obstructive pulmonary disease, chronic kidney disease (CKD), cirrhosis, uncomplicated peptic ulcer disease, and peptic ulcer bleeding (PUB), and medications e.g., nonsteroidal anti‐inflammatory drugs (NSAIDs), cyclooxygenase‐2 inhibitors, aspirin, steroids, selective serotonin reuptake inhibitors (SSRIs), warfarin and alendronate.
Results
Cox proportional hazard regression analysis showed that use of clopidogrel increased the risk of UGIB hazard ratio (HR): 3.66; 95% confidence interval (CI): 2.96–4.51 and LGIB HR: 3.52, 95% CI: 2.74–4.52. Age, CKD, PUB history, use of aspirin and NSAIDs were independent risk factors for UGIB in the clopidogrel users. Age, CKD, PUB history, use of aspirin and SSRIs were independent risk factors for LGIB.
Conclusions
In clopidogrel users, age, CKD, PUB history, use of aspirin and NSAIDs are independent risk factors for UGIB; age, CKD, PUB history, use of aspirin and SSRIs are independent risk factors for LGIB.
Recent developments in the instrumentation and data analysis of synchrotron small‐angle X‐ray scattering (SAXS) on biomolecules in solution have made biological SAXS (BioSAXS) a mature and popular ...tool in structural biology. This article reports on an advanced endstation developed at beamline 13A of the 3.0 GeV Taiwan Photon Source for biological small‐ and wide‐angle X‐ray scattering (SAXS–WAXS or SWAXS). The endstation features an in‐vacuum SWAXS detection system comprising two mobile area detectors (Eiger X 9M/1M) and an online size‐exclusion chromatography system incorporating several optical probes including a UV–Vis absorption spectrometer and refractometer. The instrumentation and automation allow simultaneous SAXS–WAXS data collection and data reduction for high‐throughput biomolecular conformation and composition determinations. The performance of the endstation is illustrated with the SWAXS data collected for several model proteins in solution, covering a scattering vector magnitude q across three orders of magnitude. The crystal‐model fittings to the data in the q range ∼0.005–2.0 Å−1 indicate high similarity of the solution structures of the proteins to their crystalline forms, except for some subtle hydration‐dependent local details. These results open up new horizons of SWAXS in studying correlated local and global structures of biomolecules in solution.
A new endstation for biological small‐ and wide‐angle X‐ray scattering is detailed, which provides development opportunities for studying correlated local and global structures of biomolecules in solution.
Electromagnetic ion cyclotron (EMIC) waves are an important mechanism for particle energization and losses inside the magnetosphere. In order to better understand the effects of these waves on ...particle dynamics, detailed information about the occurrence rate, wave power, ellipticity, normal angle, energy propagation angle distributions, and local plasma parameters are required. Previous statistical studies have used in situ observations to investigate the distribution of these parameters in the magnetic local time versus L‐shell (MLT‐L) frame within a limited magnetic latitude (MLAT) range. In this study, we present a statistical analysis of EMIC wave properties using 10 years (2001–2010) of data from Cluster, totaling 25,431 min of wave activity. Due to the polar orbit of Cluster, we are able to investigate EMIC waves at all MLATs and MLTs. This allows us to further investigate the MLAT dependence of various wave properties inside different MLT sectors and further explore the effects of Shabansky orbits on EMIC wave generation and propagation. The statistical analysis is presented in two papers. This paper focuses on the wave occurrence distribution as well as the distribution of wave properties. The companion paper focuses on local plasma parameters during wave observations as well as wave generation proxies.
Key Points
A statistical study of EMIC waves is conducted over all MLATs and MLTs
Off‐equator peaks in wave occurrence are observed in the outer magnetosphere
Wave ellipticity, normal angle, propagation angle, and wave power are also investigated