Exosomes are cell-derived vesicles containing heterogeneous active biomolecules such as proteins, lipids, mRNAs, receptors, immune regulatory molecules, and nucleic acids. They typically range in size from 30 to 150 nm in diameter. An exosome's surfaces can be bioengineered with antibodies, fluorescent dye, peptides, and tailored for small molecule and large active biologics. Exosomes have enormous potential as a drug delivery vehicle due to enhanced biocompatibility, excellent payload capability, and reduced immunogenicity compared to alternative polymeric-based carriers. Because of active targeting and specificity, exosomes are capable of delivering their cargo to exosome-recipient cells. Additionally, exosomes can potentially act as early stage disease diagnostic tools as the exosome carries various protein biomarkers associated with a specific disease. In this review, we summarize recent progress on exosome composition, biological characterization, and isolation techniques. Finally, we outline the exosome's clinical applications and preclinical advancement to provide an outlook on the importance of exosomes for use in targeted drug delivery, biomarker study, and vaccine development.
Europium ion-activated calcium silicate phosphors (Ca2SiO4:Eu3+) with sharp red-light emission were fabricated via the hydrothermal method. The size of Ca2SiO4:Eu3+ phosphors was controlled between 20 and 200 nm by precursor silicate particle sizes. Systematic studies to determine morphology, crystal phase, and photoluminescence (PL) were carried out for all the phosphors, and their optical efficiencies were compared. We found that the luminescence intensity and emission wavelength of Ca2SiO4:Eu3+ phosphors depend on their particle sizes. Particularly, the Ca2SiO4:Eu3+ synthesized with 20 nm silica seed contains the most intense red emission, high color purity, and high PL quantum yield. For the 20 nm-sized Ca2SiO4:Eu3+ phosphor, PL quantum yields are measured to be above 87.95% and high color purity of 99.8%. The unusually high intensity of 5D0 → 7F4 emission (712 nm) is explained by structural distortion arising from silicate particle size reductions. We show that the obtained phosphor is a suitable candidate for solid-state lighting as a red component through CIE chromaticity coordinate and color purity measurements. Furthermore, the Ca2SiO4:Eu3+ particles are examined for their validity as promising bio-imaging probes through cell labeling and imaging experiments and biodegradability studies.
Abstract Background Acute coronary syndrome (ACS) is rare in post-partum women. Prompt diagnosis of ACS and its etiology in postpartum women is crucial to guide the management of these complicated cases. Case summary In this case, a 37-year-old woman presented with acute chest pain. Transthoracic echocardiography revealed a large left ventricular apical thrombus. The patient underwent coronary angiography in the setting of ST segment elevation on the electrocardiogram (ECG) and troponin elevation. Coronary angiography showed a large thrombus in the proximal left anterior descending artery (LAD) with embolization to the distal (LAD) artery and distal second diagonal branch. Thrombophilia workup was unremarkable. The patient was managed with anticoagulation. Conclusion This case demonstrates an example of acute coronary syndrome in the postpartum period due to coronary artery thrombosis.
ABSTRACT We present SAMI-H i, a survey of the atomic hydrogen content of 296 galaxies with integral field spectroscopy available from the SAMI Galaxy Survey. The sample spans nearly 4 dex in stellar mass ($M_\star = 10^{7.4}-10^{11.1}~ \rm M_\odot$), redshift z < 0.06, and includes new Arecibo observations of 153 galaxies, for which we release catalogues and H i spectra. We use these data to compare the rotational velocities obtained from optical and radio observations and to show how systematic differences affect the slope and scatter of the stellar-mass and baryonic Tully–Fisher relations. Specifically, we show that $\rm H\alpha$ rotational velocities measured in the inner parts of galaxies (1.3 effective radii in this work) systematically underestimate H i global measurements, with H i/$\rm H\alpha$ velocity ratios that increase at low stellar masses, where rotation curves are typically still rising and $\rm H\alpha$ measurements do not reach their plateau. As a result, the $\rm H\alpha$ stellar mass Tully–Fisher relation is steeper (when M⋆ is the independent variable) and has larger scatter than its H i counterpart. Interestingly, we confirm the presence of a small fraction of low-mass outliers of the $\rm H\alpha$ relation that are not present when H i velocity widths are used and are not explained by ‘aperture effects’. These appear to be highly disturbed systems for which $\rm H\alpha$ widths do not provide a reliable estimate of the rotational velocity. Our analysis reaffirms the importance of taking into account differences in velocity definitions as well as tracers used when interpreting offsets from the Tully–Fisher relation, at both low and high redshifts and when comparing with simulations.
Objective This article aims to evaluate whether the use of a double-balloon catheter with oral misoprostol results in a lower rate of cesarean and shorter times to delivery than the use of the double-balloon catheter with oral placebo. Study Design In a double-blind randomized controlled trial, a double-balloon catheter was used for induction of labor with two doses of either 50 µg of misoprostol or placebo. Outcomes included cesarean rate, time to vaginal delivery, change in Bishop's score, and oxytocin usage. Results A total of 343 women were screened and 199 randomized: 99 to the misoprostol arm and 100 to the placebo arm. Cesarean delivery rate was not different between the groups (misoprostol: 13.1% vs. placebo: 17.0%, p = 0.45). Time to vaginal delivery was significantly shorter (mean: 14.6 ± 6.9 vs. 20.8 ± 13.8 hours, p < 0.0001), change in Bishop's score was significantly greater (median: 5 vs. 4 points, p = 0.005), and use of oxytocin was significantly less frequent (86.9 vs. 98.0% patients, p = 0.01) in the misoprostol group. Conclusion The use of a double-balloon catheter with oral misoprostol for induction did not reduce the cesarean delivery rate, but did result in shorter labors, a greater increase in Bishop's score, and a lower need for oxytocin use.
Dysregulated myeloid cell activity underlies a variety of pathologies, including immunosuppression in malignant cancers. Current treatments to alter myeloid cell behavior also alter other immune cell subpopulations and nonimmune cell types with deleterious side effects. Therefore, improved selectivity of myeloid treatment is an urgent need. To meet this need, we demonstrate a novel, targeted nanoparticle system that achieves superior myeloid selectivity both in vitro and in vivo. This system comprises: (1) granulocyte-colony stimulating factor (G-CSF) as a targeting ligand to promote accumulation in myeloid cells, including immunosuppressive myeloid-derived suppressor cells (MDSCs); (2) albumin nanoparticles 100-120 nm in diameter that maintain morphology and drug payload in simulated physiological conditions; and (3) a fluorophore that enables nanoparticle tracking and models a therapeutic molecule. Here, we show that this strategy achieves high myeloid uptake in mixed primary immune cells and that nanoparticles successfully infiltrate the 4T1 triple-negative breast tumor murine microenvironment, where they preferentially accumulate in myeloid cells in a mouse model. Further development will realize diagnostic myeloid cell tracking applications and therapeutic delivery of myeloid-reprogramming drugs.