We tested the hypothesis that combined xenogenic (from mini-pig) adipose-derived mesenchymal stem cell (ADMSC) and ADMSC-derived exosome therapy could reduce brain-infarct zone (BIZ) and enhance neurological recovery in rat after acute ischemic stroke (AIS) induced by 50-min left middle cerebral artery occlusion. Adult-male Sprague-Dawley rats (n = 60) were divided equally into group 1 (sham-control), group 2 (AIS), group 3 [AIS-ADMSC (1.2×106 cells)], group 4 [AIS-exosome (100μg)], and group 5 (AIS-exosome-ADMSC). All therapies were provided intravenously at 3h after AIS procedure. BIZ determined by histopathology (by day-60) and brain MRI (by day-28) were highest in group 2, lowest in group 1, higher in groups 3 and 4 than in group 5, but they showed no difference between groups 3 and 4 (all p < 0.0001). By day-28, sensorimotor functional results exhibited an opposite pattern to BIZ among the five groups (p < 0.005). Protein expressions of inflammatory (inducible nitric oxide synthase/tumor necrosis factor-α/nuclear factor-κB/interleukin-1β/matrix metalloproteinase-9/plasminogen activator inhibitor-1/RANTES), oxidative-stress (NOX-1/NOX-2/oxidized protein), apoptotic (caspase-3/ Poly-ADP-ribose polymerase), and fibrotic (Smad3/transforming growth factor-β) biomarkers, and cellular expressions of brain-damaged (γ-H2AX+/ XRCC1-CD90+/p53BP1-CD90+), inflammatory (CD11+/CD68+/glial fibrillary acid protein+) and brain-edema (aquaporin-4+) markers showed a similar pattern of BIZ among the groups (all n < 0.0001). In conclusion, xenogenic ADMSC/ADMSC-derived exosome therapy was safe and offered the additional benefit of reducing BIZ and improving neurological function in rat AIS.
We tested the hypothesis that allogenic adipose-derived mesenchymal stem cells (ADMSCs) alleviated brain death (BD)-induced remote organ damage and events of post heart-transplant acute rejection. To determine the impact of BD on remote organ damage, adult-male F344 rats (n=24) were categorized sham-control (SC), BD and BDMSC (allogenic ADMSC/1.2 × 106 cells/derived from F344 by intravenous transfusion 3 h after BD procedure). To determine the protective effect of allogenic ADMSCs, animals (n=8/each group in F344/Lewis) were categorized into groups BD-T(F344 heart transplanted into Lewis by 6h after BD), BD-TMSC(D1/3) (BD induction for 6h then heart transplantation, and allogenic ADMSCs transfusion at days 1 and 5 after heart transplantation), BD-TMSC(3h) (BD + ADMSC/1.2 × 106 cells at 3h and heart transplantation at 6h after BD) and BD-TMSC(3h, D1/3) [BD + ADMSC/1.2 × 106 cells at 3h and heart transplantation at 6h after BD, then ADMSC therapy by days 1/3]. At day 5 post procedure, liver, kidney and heart specimens showed higher molecular-cellular levels of inflammation, immune reaction, apoptosis and fibrosis in BD than in SC that were reversed in BDMSC (all P < 0.0001). These molecular-cellular expressions and circulating/splenic levels of innate/adoptive immune cells were higher in BD-T, lowest in BD-TMSC(3h, D1/3) and higher BD-TMSC(3h) in than BD-TMSC(D1/3), whereas heart function showed an opposite pattern among the four groups (all P < 0.001). In conclusion, ADMSCs suppressed BD-caused remote organ damage and heart-transplant rejection.
Diamond nitrogen-vacancy (NV) center-based magnetometry provides a unique opportunity for quantum bio-sensing. However, NV centers are not sensitive to parameters such as temperature and pressure, and immune to many biochemical parameters such as pH and non-magnetic biomolecules. Here, we propose a scheme that can potentially enable the measurement of various biochemical parameters using diamond quantum sensing, by employing stimulus-responsive hydrogels as a spacing transducer in-between a nanodiamond (ND, with NV centers) and magnetic nanoparticles (MNPs). The volume phase transition of hydrogel upon stimulation leads to sharp variation in the separation distance between the MNPs and the ND. This in turn changes the magnetic field that the NV centers can detect sensitively. We construct a temperature sensor under this hybrid scheme and show the proof-of-the-principle demonstration of reversible temperature sensing. Applications in the detection of other bio-relevant parameters are envisioned if appropriate types of hydrogels can be engineered.
Energy transfer (ET) is an important route to manage the population density of excited states, giving rise to spectrally tunable emission that is valuable for multicolor imaging and biological tracking. In this paper, a case study of GdF3 nanoparticles (NPs) codoped with Yb3+ and Er3+ was used to experimentally and theoretically investigate the ET mechanisms under near-infrared and violet excitation. Red-to-green ratio (RGR) is used as a primary evaluating protocol, and the power-dependent luminescence and Er3+ 4I13/2 luminescence behavior are used to identify the corresponding conjectures about ET mechanisms. Compared with the four common upconversion (UC) models, a joint effect of energy-back-transfer, multiphonon relaxation, and linear decay depletion mechanisms for the Er3+ 4I13/2 manifold was proposed for the UC process based on UC spectra for samples with different dopant concentrations. Meanwhile, the varying RGR could also be observed from downshifting (DS) emission spectra. The ET mechanism for the DS process, where three cross-relaxation processes coexisted including the Yb3+ 2F5/2 manifold as energy in-transit state, was proposed for the first time. The findings are expected to provide an approach for understanding ET mechanisms in many Yb3+/Er3+ codoped UC and DS systems and enable spectrally tunable emission properties for applications that require precisely defined optical transitions.
This study tested for the benefits of early administration of carvedilol as protection against doxorubicin (DOX)-induced cardiomyopathy. Thirty male, adult B6 mice were categorized into group 1 (untreated control), group 2 [DOX treatment (15 mg/every other day for 2 weeks, i.p.], and group 3 [carvedilol (15 mg/kg/d, from day 7 after DOX treatment for 28 days)], and euthanized by day 35 after DOX treatment. By day 35, the left ventricular ejection fraction (LVEF) was significantly lower in group 2 than in groups 1 and 3, and significantly lower in group 3 than in group 1, whereas the left ventricular (LV) end-diastolic and LV endsystolic dimensions showed an opposite pattern to the LVEF among the three groups. The protein expressions of fibrotic (Smad3, TGF-b), apoptotic (BAX, cleaved caspase 3, PARP), DNA damage (g-H2AX), oxidative stress (oxidized protein), mitochondrial damage (cytosolic cytochrome-C), heart failure (brain natriuretic peptide), and hypertrophic (b-MHC) biomarkers of the LV myocardium showed an opposite pattern to the LVEF among the three groups. The protein expressions of antifibrotic (BMP-2, Smad1/5), a-MHC, and phosphorylated-Akt showed an identical pattern to the LVEF among the three groups. The microscopic findings of fibrotic and collagen-deposition areas and the numbers of g-H2AX 1 and 53BP1 1 cells in the LV myocardium exhibited an opposite pattern, whereas the numbers of endothelial cell (CD31 1 , vWF 1 ) markers showed an identical pattern to the LVEF among the three groups. Cardiac stem cell markers (C-kit 1 and Sca-1 1 cells) were significantly and progressively increased from group 1 to group 3. Additionally, the in vitro study showed carvedilol treatment significantly inhibited DOX-induced cardiomyoblast DNA (CD90/ XRCC11 , CD90/53BP1 1 , and r-H2AX 1 cells) damage. Early carvedilol therapy protected against DOX-induced DNA damage and cardiomyopathy.
BackgroundObesity is an important cardiovascular risk factor. This study tested the effect of obesity reduction on preserving left ventricular ejection fraction (LVEF) and attenuating inflammation, oxidative stress and LV remodeling in obese mice.Methods and resultsEight-week-old C57BL/6 J mice (n=24) were equally divided into control (fed a control diet for 22 weeks), obesity (high-fat diet, 22 weeks), and obese reduction (OR) (high-fat diet, 14 weeks; then control diet, 8 weeks). Animals were sacrificed at post 22-week high-fat diet and the LV myocardium collected. Heart weight, body weight, abdominal-fat weight, total cholesterol level and fasting blood glucose were higher in obesity than in control and OR (all p<0.001). Inflammation measured by mRNA expressions of IL-6, MMP-9, PAI-1 and leptin and protein expression of NF-κB was higher, whereas anti-inflammation measured by mRNA expressions of adiponectin and INF-γ was lower in obesity than in control and OR (all p<0.003). Oxidative protein expressions of NOX-1, NOX-2 and oxidized protein were higher, whereas expression of anti-oxidant markers HO-1 and NQO-1 were lower (all p<0.01); and apoptosis measured by Bax and caspase 3 was higher, whereas anti-apoptotic Bcl-2 was lower in obesity as compared with control and OR (all p<0.001). The expressions of fibrotic markers phosphorylated Smad3 and TGF-β were higher, whereas expression of anti-fibrotic phosphorylated Smad1/5 and BMP-2 were lower (all p<0.02); and LVEF was lower, whereas the LV remodeling was higher in obesity than in control and OR (all p<0.001).ConclusionImpaired LVEF, enhanced LV remodeling, inflammation, fibrosis, oxidative stress and apoptosis were reversed by reduction in mouse obesity.
Nitrogen-vacancy (NV) centers in diamond are promising quantum sensors for their long spin coherence time under ambient conditions. However, their spin resonances are relatively insensitive to non-magnetic parameters such as temperature. A magnetic-nanoparticle-nanodiamond hybrid thermometer, where the temperature change is converted to the magnetic field variation near the Curie temperature, was demonstrated to have enhanced temperature sensitivity ($11{\rm{\;mK\;H}}{{\rm{z}}^{ - 1/2}}$) [Phys. Rev. X 8, 011042 (2018)], but the sensitivity was limited by the large spectral broadening of ensemble spins in nanodiamonds. To overcome this limitation, here we show an improved design of a hybrid nanothermometer using a single NV center in a diamond nanopillar coupled with a single magnetic nanoparticle of copper-nickel alloy, and demonstrate a temperature sensitivity of $76{\rm{\;\mu K\;H}}{{\rm{z}}^{ - 1/2}}$. This hybrid design enables detection of 2 millikelvin temperature changes with temporal resolution of 5 milliseconds. The ultra-sensitive nanothermometer offers a new tool to investigate thermal processes in nanoscale systems.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.