Synthesis of NaYF4:Yb3+, Er3+ upconversion nanoparticles in normal microemulsions

An interface-controlled reaction in normal microemulsions (water/ethanol/sodium oleate/oleic acid/n-hexane) was designed to prepare NaYF4:Yb3+, Er3+ upconversion nanoparticles. The phase diagram of the system was first studied to obtain the appropriate oil-in-water microemulsions. Transmission electron microscopy and X-ray powder diffractometer measurements revealed that the as-prepared nanoparticles were spherical, monodisperse with a uniform size of 20 nm, and of cubic phase with good crystallinity. Furthermore, these nanoparticles have good dispersibility in nonpolar organic solvents and exhibit visible upconversion luminescence of orange color under continuous excitation at 980 nm. Then, a thermal treatment for the products was found to enhance the luminescence intensity. In addition, because of its inherent merit in high yielding and being economical, this synthetic method could be utilized for preparation of the UCNPs on a large scale

Nesiritide protects endothelial function after ballooninduced trauma in the iliac artery in rabbits

To assess the effect of nesiritide on the endothelial function of iliac arteries following endothelia trauma. Right iliac artery trauma was created with a balloon catheter. Ten rabbits were treated with a 4-week subcutaneous injection of nesiritide at a fixed daily dose of 0.1mg/kg. Ten rabbits received daily normal saline injection. Plasma endothelin 1 (ET-1), nitric oxide (NO), and Von Willebrand Factor (vWF) were measured before and after the therapies. Tissue proliferating cell nuclear antigen (PCNA) was measured after the treatment. After the treatment, in the therapeutic group, the area under internal elastic membrane and the residual lumen area were higher than in the normal saline group (P <0.05). The plasma levels of ET-1 (91.6±6.8 vs 114.9±6.3 ng/L, P =0.001), vWF (134.6±10.8% vs 188.8±10.4%, P =0.001) and the ratio of PCNA positive expression (11.7±4.2% vs 36.2±11.4%, P =0.005) in the therapeutic group was lower than in the normal saline group, while the plasma levels of NO was higher (89.7±9.3 vs 43.5±5.3 μmol/L, P =0.001). Nesiritide inhibited remodeling of rabbit iliac artery following endothelial trauma. The inhibition of vascular remodeling may be related to the alleviated endothelial dysfunction and reduced expression of tissue proliferating cell nuclear antigen

Trifluoromethyl-phenyl-triazolyl derivative of beta-bisabolol induces cell death in ME-180 cervical cancer cells through induction of apoptosis and ROS generation

The aim of the current investigation was to design, synthesize and demonstrate the anticancer and apoptotic activity of trifluoromethyl-phenyl-triazolyl derivative of beta-bisabolol (TTB) in ME-180 human cervical cancer cells.  MTT and clonogenic assays were used to evaluate the cell viability and colony formation tendencies of the cells respectively. Phase contrast and fluorescence microscopic investigations were used to evaluate the effect of TTB on cellular morphology and apoptosis. Flow cytometric analysis using fluorescent CM-DCFH2-DA were used to study the effect of TTB on reactive oxygen species (ROS) formation. The results revealed that TTB significantly inhibited the proliferation of ME-180 human cervical cancer cells in a time-dependent as well as dose-dependent manner. TTB has the capacity to inhibit both anchorage dependent as well as anchorage independent growth of ME-180 cervical cancer cells. TTB-treated cells revealed chromatin condensation, fragmented nuclei and nuclear shrinkage. A 3-fold increase of ROS production was seen after 72 ?M TTB treatment. Video Clip of Methodology: Phase contrast microscopic study:  2 min   Full Screen   Alternat

Proteomic analysis of sex conversion induced by CPPU in male grapevine of Vitis amurensis

If N-(2-chloro-4-pyridyl)-N′-phenylurea (CPPU) could induce sex conversion in male plants of Vitis amurensis Rupr., this would reduce blindness of selection for male parents according to the fruit characters in cold-tolerant and disease-tolerant grape crossbreeding. Flower bud samples of male plants were treated with 100 mg∙L-1 CPPU at 15 days before anthesis. Two-dimensional gel electrophoresis (2-DE) was used to analyze the proteins related to sex conversion at different development time points. More than 600 protein spots were detected. Among them, 31 differentially expressed proteins were identified by MALDI-TOF/TOF, and 24 protein spots could be assigned to a probable function. Seventeen proteins participated in the sex conversion and with complex interaction. Sex conversion might receive the ROS signal in the beginning, and then pollen tube proteins were proposed to down-regulate to repress the stamen development, while the up-regulated cell elongation protein might promote the development of pistil. Adenine phosphoribosyl transferase 3 was proposed as the key protein in the sex organ conversion that was up-regulated by CPPU in the male V. amurensis achieving the ability to fruit in the end.

Neuroprotective Effect of Ginkgolide B on Bupivacaine-Induced Apoptosis in SH-SY5Y Cells

Local anesthetics are used routinely and effectively. However, many are also known to activate neurotoxic pathways. We tested the neuroprotective efficacy of ginkgolide B (GB), an active component of Ginkgo biloba, against ROS-mediated neurotoxicity caused by the local anesthetic bupivacaine. SH-SY5Y cells were treated with different concentrations of bupivacaine alone or following preincubation with GB. Pretreatment with GB increased SH-SY5Y cell viability and attenuated intracellular ROS accumulation, apoptosis, mitochondrial dysfunction, and ER stress. GB suppressed bupivacaine-induced mitochondrial depolarization and mitochondria complex I and III inhibition and increased cleaved caspase-3 and Htra2 expression, which was strongly indicative of activation of mitochondria-dependent apoptosis with concomitantly enhanced expressions of Grp78, caspase-12 mRNA, protein, and ER stress. GB also improved ultrastructural changes indicative of mitochondrial and ER damage induced by bupivacaine. These results implicate bupivacaine-induced ROS-dependent mitochondria, ER dysfunction, and apoptosis, which can be attenuated by GB through its antioxidant property

Searching for candidates of coalescing binary black holes formed through chemically homogeneous evolution in GWTC-3

The LIGO, Virgo, and KAGRA (LVK) collaboration has announced 90 coalescing binary black holes (BBHs) with $p_{\rm astro} > 50\%$ to date, however, the origin of their formation channels is still an open scientific question. Given various properties of BBHs (BH component masses and individual spins) inferred using the default priors by the LVK, independent groups have been trying to explain the formation of the BBHs with different formation channels. Of all formation scenarios, the chemically homogeneous evolution (CHE) channel has stood out with distinguishing features, namely, nearly-equal component masses and preferentially high individual spins aligned with the orbital angular momentum. We perform Bayesian inference on the BBH events officially reported in GWTC-3 with astrophysically-predicted priors representing different formation channels of the isolated binary evolution (CEE: common-envelope evolution channel; CHE; SMT: stable mass transfer). Given assumed models, we report strong evidence for GW190517\_055101 being most likely to have formed through the CHE channel. Assuming the BBH events in the subsample are all formed through one of the isolated binary evolution channels, we obtain the lower limits on the local merger rate density of these channels at $11.45 ~\mathrm{Gpc^{-3}~yr^{-1}}$ (CEE), $0.18 ~\mathrm{Gpc^{-3}~yr^{-1}}$ (CHE), and $0.63 ~\mathrm{Gpc^{-3}~yr^{-1}}$ (SMT) at $90\%$ credible level.Comment: 13 pages, 4 figures, 1 tabl

Clinical significance of episcleral venous fluid wave in gonioscopy-assisted transluminal trabeculotomy

AIM: To evaluate the clinical significance of checking episcleral venous fluid wave (EVFW) during gonioscopy-assisted transluminal trabeculotomy (GATT) in patients with open angle glaucoma (OAG). METHODS: This retrospective case series study comprised 30 patients (45 eyes) with OAG underwent GATT. The location and extent of EVFW were examined and graded after intraoperative compression flushing of the anterior chamber angle during the operation. Patients were followed up for 1y. A complete success for surgery is defined as a postoperative intraocular pressure (IOP) <18 mm Hg without any anti-glaucoma medication. IOP<18 mm Hg with less than two anti-glaucoma medications is defined as qualified success, while the control of IOP requiring three anti-glaucoma medications is considered as unsuccess. RESULTS: The mean IOP was 35.38±7.16 mm Hg before surgery and 15.52±4.22 mm Hg 1y after surgery (P<0.01). The average number of anti-glaucoma medication was 2.8±1.2 (2-4) preoperation and 0.6±1.3 (0-3) 1y postoperation (P<0.01). The success rate of the operation was 93.33%. Complete success rate was 66.67%, qualified success rate was 26.67%, and 6.66% of unsuccessful cases required reoperation. EVFW of all cases was grade 2-4, and the percentages of grade 2, 3 and 4 were 33.33%, 40.0% and 26.67%, respectively. The distribution and percentage of EVFW were inferior (36%), nasal (28%), superior (20%), and temporal (16%). The EVFW grade of complete success patients was 3.4±0.6 (3-4), and that of qualified success patients was 2.6±1.0 (2-4). The larger the range of EVFW, the lower the IOP, and the better the IOP reduction effect. CONCLUSION: During GATT surgery, pressurized irrigation of anterior chamber to check EVFW can reduce the outflow resistance of aqueous humor and increase the effect of postoperative IOP. The range of EVFW is negatively correlated with postoperative IOP. Therefore, EVFW may be a valuable prognostic indicator for the success of GATT surgery

Isostructural Phase Transition of TiN Under High Pressure

In situ high-pressure energy dispersive x-ray diffraction experiments on polycrystalline powder TiN with NaCl-type structure have been conducted with the pressure up to 30.1 GPa by using the diamond anvil cell instrument with synchrotron radiation at room tempearture. The experimental results suggested that an isostructural phase transition might exist at about 7 GPa as revealed by the discontinuity of V/V0 with pressure.Comment: submitte

A possible 250-second X-ray quasi-periodicity in the fast blue optical transient AT2018cow

The fast blue optical transients (FBOTs) are a new population of extragalactic transients of unclear physical origin. A variety of mechanisms have been proposed including failed supernova explosion, shock interaction with a dense medium, young magnetar, accretion onto a compact object, and stellar tidal disruption event, but none is conclusive. Here we report the discovery of a possible X-ray quasi-periodicity signal with a period of $\sim$250 second (at a significance level of 99.76%) in the brightest FBOT AT2018cow through the analysis of XMM-Newton/PN data. The signal is independently detected at the same frequency in the average power density spectrum from data taken from the Swift telescope, with observations covering from 6 to 37 days after the optical discovery, though the significance level is lower (94.26%). This suggests that the QPO frequency may be stable over at least 1.1$\times$ 10$^{4}$ cycles. Assuming the $\sim$250 second QPO to be a scaled-down analogue of that typically seen in stellar mass black holes, a black hole mass of $\sim10^{3}-10^{5}$ solar masses could be inferred. The overall X-ray luminosity evolution could be modeled with the stellar tidal disruption by a black hole of $\sim10^4$ solar masses, providing a viable mechanism to produce AT2018cow. Our findings suggest that other bright FBOTs may also harbor intermediate-mass black holes.Comment: 18 pages, 10 figures. Accepted for publication in Research in Astronomy and Astrophysic

Identifying central symptom clusters and correlates in children with acute leukemia undergoing chemotherapy: a network analysis

BackgroundPrevious studies have examined symptom clusters in children with acute leukemia, yet a knowledge gap persists regarding central symptom clusters and their influencing factors. By identifying these central clusters and associated factors, healthcare providers can enhance their understanding and effective management of symptoms. Our study seeks to address this gap by identifying symptom clusters, exploring central clusters, and investigating the demographic and health-related factors associated with these clusters in children with acute leukemia undergoing chemotherapy.MethodsA total of 586 children with acute leukemia from January 2021 to April 2023 were recruited from China. They were investigated using Memorial Symptom Assessment Scale 10-18 during chemotherapy. The principal component analysis was used to identify the symptom clusters. An association network was conducted to describe the relationships among symptoms and clusters. A multiple linear model was used to investigate the associated factors for the severity of overall symptoms and each symptom cluster.ResultsFive clusters were identified, including oral and skin cluster, somatic cluster, self-image disorder cluster, gastrointestinal cluster and psychological cluster. Gastrointestinal cluster was the most central symptom cluster. Age, sex, clinical classification, number of having chemotherapy and education degree and marital status of the primary caregiver are associated with the severity of these five symptom clusters.ConclusionOur study highlights the importance of evaluating symptom clusters in children with acute leukemia during chemotherapy. Specifically, addressing gastrointestinal symptoms is crucial for effective symptom management and overall care