Effect of Ambient Conditions on Acoustic Activation of the Perfluoropropane Droplets Within the Infarct Zone.

BACKGROUND: Acoustically activated perfluoropropane droplets (PD) formulated from lipid encapsulated microbubble preparations produce a delayed myocardial contrast enhancement that preferentially highlights the infarct zones (IZ). Since activation of PDs may be temperature sensitive, it is unclear what effect body temperature (BT) has on acoustic activation (AA). OBJECTIVE: We sought to determine whether the microvascular retention and degree of myocardial contrast intensity (MCI) would be affected by BT at the time of intravenous injection. METHODS: We administered intravenous (IV) PD in nine rats following 60 min of ischemia followed by reperfusion. Injections in these rats were given at temperatures above and below 36.5°C, with high MI activation in both groups at 3 or 6 min following IV injection (IVI). In six additional rats (three in each group), IV PDs were given only at one temperature (<36.5°C or ≥36.5°C), permitting a total of 12 comparisons of different BT. Differences in background subtracted MCI at 3-6 min post-injection were compared in the infarct zone (IZ) and remote zone (RZ). Post-mortem lung hematoxylin and eosin (H&E) staining was performed to assess the effect potential thermal activation on lung tissue. RESULTS: Selective MCI within the IZ was observed in 8 of 12 rats who received IVI of PDs at <36.5°C, but none of the 12 rats who had IVI at the higher temperature (p < 0.0001). Absolute MCI following droplet activation was significantly higher in both the IZ and RZ when given at the lower BT. H&E indicated significant red blood extravasation in 5/7 rats who had had IV injections at higher BT, and 0/7 rats who had IV PDs at <36.5°C. CONCLUSIONS: Selective IZ enhancement with AA of intravenous PDs is possible, but temperature sensitive. Thermal activation appears to occur when PDs are given at higher temperatures, preventing AA, and increasing unwanted bioeffects.

Corrigendum: Integrated analysis of transcriptome and metabolome reveals the mechanism of chlorine dioxide repressed potato (Solanum tuberosum L.) tuber sprouting.

[This corrects the article DOI: 10.3389/fpls.2022.887179.].

Acoustic Activation Imaging With Intravenous Perfluoropropane Nanodroplets Results in Selective Bioactivation of the Risk Area.

BACKGROUND: Acoustically activatable perfluoropropane droplets (PD) can be formulated from commercially available microbubble preparations. Diagnostic transthoracic ultrasound frequencies have resulted in acoustic activation (AA) predominately within myocardial infarct zones (IZ). OBJECTIVE: We hypothesized that the AA area following acute coronary ischemia/reperfusion (I/R) would selectively enhance the developing scar zone, and target bioeffects specifically to this region. METHODS: We administered intravenous PD in 36 rats and 20 pigs at various stages of myocardial scar formation (30 minutes, 1 day, and 7 days post I/R) to determine what effect infarct age had on the AA within the IZ. This was correlated with histology, myeloperoxidase activity, and tissue nitrite activity. RESULTS: The degree of AA within the IZ in rats was not associated with collagen content, neutrophil infiltration, or infarct age. AA within 24 hours of I/R was associated with increased nitric oxide utilization selectively within the IZ (P < .05 compared with remote zone). The spatial extent of AA in pigs correlated with infarct size only when performed before sacrifice at 7 days (r = .74, P < .01). CONCLUSIONS: Acoustic activation of intravenous PD enhances the developing scar zone following I/R, and results in selective tissue nitric oxide utilization.

The Postharvest Application of Carvone, Abscisic Acid, Gibberellin, and Variable Temperature for Regulating the Dormancy Release and Sprouting Commencement of Mini-Tuber Potato Seeds Produced under Aeroponics.

This study investigated the efficacy of carvone, abscisic acid (ABA), gibberellin (GA3), and variable temperature in managing dormancy and sprouting in aeroponically grown mini-tuber potato (Solanum tuberosum L.) seeds. The results showed that carvone treatment effectively reduced the weight loss rate by 12.25% and decay rate by 3.33% at day 25 compared to control. ABA treatment significantly enhanced the germination rate, increasing it to 97.33%. GA3 treatment resulted in the longest sprouts of 14.24 mm and reduced the MDA content by 23.08% at day 30, indicating its potential in shortening dormancy and maintaining membrane integrity. The variable-temperature treatment demonstrated a balanced performance in reducing weight loss and maintaining a lower relative conductivity, indicating less cellular damage. The enzymatic activities of α-amylase, CAT, and SOD were modulated by the treatments, ensuring a balanced enzymatic environment for seed vitality. These results establish a solid basis for improving postharvest management strategies to optimize germination uniformity and preserve the quality of aeroponic potato seeds during extended dormancy, promising enhanced yield and productivity in potato cultivation.

Nicotine exacerbates endothelial dysfunction and drives atherosclerosis via extracellular vesicle-miRNA.

AIMS: Nicotine, a major component of tobacco, is an important factor contributing to atherosclerosis. However, the molecular mechanisms underlying the link between nicotine and atherosclerosis are unclear. As extracellular vesicles (EVs) are involved in intercellular communication in atherosclerosis, we investigated whether their influence on arterial pathophysiology under nicotine stimulation. METHODS AND RESULTS: EVs from the serum of smokers (smoker-EVs) were significantly increased and exacerbated endothelial inflammation, as well as apoptosis according to functional studies. Meanwhile, inhibition of EVs blunted the nicotine-induced atherosclerosis progression, and injection of nicotine-induced EVs promoted atherosclerosis progression in ApoE-/- mice. Furthermore, quantitative reverse transcription-polymerase chain reaction analysis revealed a remarkable increase in miR-155 levels in smoker-EVs, which was correlated with carotid plaque formation in patients measured by ultrasound imaging. Moreover, CD14 levels were significantly increased in EVs from smokers (representing EVs derived from monocytes), indicating that monocytes are an important source of smoker-EVs. DNA methylation and the transcription factor HIF1α may contribute to increased miR-155 levels in monocytes, as assessed with bisulfite conversion sequencing and chromatin immunoprecipitation. Mechanistically, EVs encapsulated miR-155 induced endothelial cell dysfunction by directedly targeting BCL2, MCL1, TIMP3, BCL6, and activating NF-κB pathway, as verified in a series of molecular and biological experiments. Injecting EVs from nicotine-stimulated monocytes promoted plaque formation and triggered vascular endothelial injury in ApoE-/- mice, whereas inhibition of miR-155 weakened this effect. CONCLUSION: Our findings revealed an EV-dependent mechanism of nicotine-aggravated atherosclerosis. Accordingly, we propose an EV-based intervention strategy for atherosclerosis management.

Unraveling the mechanism of potato (Solanum tuberosum L.) tuber sprouting using transcriptome and metabolome analyses.

Sprouting is an irreversible deterioration of potato quality, which leads to the production of harmful toxins and loss of the commercial value of potatoes. However, there is no report on the changes in different stages of potato sprouting through transcriptome and metabonomics. In this study, 1471 differentially expressed genes (DEGs) were found between DP and BP. In comparison with SP, a total of 6309 DEGs were detected in BP. Additionally, 6624 DEGs were identified between DP and SP. Moreover, 96 and 117 differentially accumulated metabolites (DAMs) were detected between DP and BP and between BP and SP, respectively. Furthermore, 130 DAMs were identified in total between DP and SP. In each group, a correlation analysis of DAMs and DEGs was performed to examine the regulatory network. The results indicated that the sprouting of tubers is mainly regulated by plant hormone signals, and during the sprouting of tubers, significant changes in metabolic products occur in the body. According to the combined analysis of transcriptomics and metabolomics, multiple metabolites were both positive and negative regulated by genes.

Acoustic Detection of Retained Perfluoropropane Droplets Within the Developing Myocardial Infarct Zone.

Perfluoropropane droplets (PDs) cross endothelial barriers and can be acoustically activated for selective myocardial extravascular enhancement following intravenous injection (IVI). Our objective was to determine how to optimally activate extravascular PDs for transthoracic ultrasound-enhanced delineation of a developing scar zone (DSZ). Ultrafast-frame-rate microscopy was conducted to determine the effect of pulse sequence on the threshold of bubble formation from PDs. In vitro studies were subsequently performed at different flow rates to determine acoustic activation and inertial cavitation thresholds for a PD infusion using multipulse fundamental non-linear or single-pulse harmonic imaging. IVIs of PDs were given in 9 rats and 10 pigs following prolonged left anterior descending ischemia to detect and quantify PD kinetics within the DSZ. A multipulse sequence had a lower myocardial index threshold for acoustic activation by ultrafast-frame-rate microscopy. Acoustic activation was observed at a myocardial index ≥0.4 below the inertial cavitation threshold for both pulse sequences. In rats, confocal microscopy and serial acoustic activation imaging detected higher droplet presence (relative to remote regions) within the DSZ at 3 min post-IVI. Transthoracic high-mechanical-index impulses with fundamental non-linear imaging in pigs at this time post-IVI resulted in selective contrast enhancement within the DSZ.

Integrated Analysis of Transcriptome and Metabolome Reveals the Mechanism of Chlorine Dioxide Repressed Potato (Solanum tuberosum L.) Tuber Sprouting.

Sprouting is an irreversible deterioration of potato quality, which not only causes loss in their commercial value but also produces harmful toxins. As a popular disinfectant, ClO2 can inhibit the sprouting of potato tubers. Using transcriptomic and metabolomic approaches to understand the repressive mechanism of ClO2 in potato sprouting is yet to be reported. Sequencing the transcriptome and metabolome of potatoes treated with ClO2 in this study revealed a total of 3,119 differentially expressed genes, with 1,247 and 1,872 genes showing down- and upregulated expression, respectively. The majority of the downregulated genes were associated with plant hormone signal transduction, whereas upregulated differential genes were associated primarily with biological processes, such as phenylpropanoid biosynthesis and the mitogen-activated protein kinase (MAPK) signaling pathway. Metabonomic assays identified a total of 932 metabolites, with 33 and 52 metabolites being down- and upregulated, respectively. Downregulated metabolites were mostly alkaloids, amino acids, and their derivatives, whereas upregulated metabolites were composed mainly of flavonoids and coumarins. Integrated transcriptomic and metabolomic analyses showed that many different metabolites were regulated by several different genes, forming a complex regulatory network. These results provide new insights for understanding the mechanism of ClO2-mediated repression of potato sprouting.

Study on the Structure, Magnetic Properties and Mechanism of Zn-Doped Yttrium Iron Garnet Nanomaterial Prepared by the Sol-gel Method.

To explore the effect and mechanism of bivalent ion doping on yttrium iron garnet (YIG), Zn-YIG (Zn-doped YIG) nanoparticles with a size of 60~70 nm were prepared by the sol-gel method. It was proven that Zn ion doping resulted in lattice expansion and internal stress due to crystallite size shrinkage. A Raman spectroscopic analysis proved the influence of Zn doping on the crystal structure and peak intensity by analyzing Raman vibration modes. The characteristics and chemical mechanism of mass loss and phase evolution in each temperature region were explored through TG-DSC measurements. Moreover, it was revealed that the antiferromagnetic coupling, pinning mechanisms and particle aggregation lead to coercivity, exhibiting different variation trends. A saturation magnetization (Ms) curve variation mechanism was further revealed, which was due to the thermal effects, super-exchange effect, and coupling effect between sub-lattices. Meanwhile, the influence of the thermal effect on Ms and its mechanism were explored by spin theory, and it was proven that it was mainly caused by the random arrangement of magnetic moments and thermal vibration. These results provide theoretical support for the wider application of YIG devices in microwave and high-temperature fields.

Nomograms based on preoperative multimodal ultrasound of papillary thyroid carcinoma for predicting central lymph node metastasis.

OBJECTIVES: To establish a nomogram for predicting central lymph node metastasis (CLNM) based on the preoperative clinical and multimodal ultrasound (US) features of papillary thyroid carcinoma (PTC) and cervical LNs. METHODS: Overall, 822 patients with PTC were included in this retrospective study. A thyroid tumor ultrasound model (TTUM) and thyroid tumor and cervical LN ultrasound model (TTCLNUM) were constructed as nomograms to predict the CLNM risk. Areas under the curve (AUCs) evaluated model performance. Calibration and decision curves were applied to assess the accuracy and clinical utility. RESULTS: For the TTUM training and test sets, the AUCs were 0.786 and 0.789 and bias-corrected AUCs were 0.786 and 0.831, respectively. For the TTCLNUM training and test sets, the AUCs were 0.806 and 0.804 and bias-corrected AUCs were 0.807 and 0.827, respectively. Calibration and decision curves for the TTCLNUM nomogram exhibited higher accuracy and clinical practicability. The AUCs were 0.746 and 0.719 and specificities were 0.942 and 0.905 for the training and test sets, respectively, when the US tumor size was ≤ 8.45 mm, while the AUCs were 0.737 and 0.824 and sensitivity were 0.905 and 0.880, respectively, when the US tumor size was > 8.45 mm. CONCLUSION: The TTCLNUM nomogram exhibited better predictive performance, especially for the CLNM risk of different PTC tumor sizes. Thus, it serves as a useful clinical tool to supply valuable information for active surveillance and treatment decisions. KEY POINTS: • Our preoperative noninvasive and intuitive prediction method can improve the accuracy of central lymph node metastasis (CLNM) risk assessment and guide clinical treatment in line with current trends toward personalized treatments. • Preoperative clinical and multimodal ultrasound features of primary papillary thyroid carcinoma (PTC) tumors and cervical LNs were directly used to build an accurate and easy-to-use nomogram for predicting CLNM. • The thyroid tumor and cervical lymph node ultrasound model exhibited better performance for predicting the CLNM of different PTC tumor sizes. It may serve as a useful clinical tool to provide valuable information for active surveillance and treatment decisions.

Assessment of Left Ventricular Global Myocardial Work in Patients With Different Degrees of Coronary Artery Stenosis by Pressure-Strain Loops Analysis.

Global myocardial work (MW) analysis by pressure-strain loops (PSL) allows the non-invasive assessment of left ventricular (LV) function. We aimed to investigate the relationship between LV global MW and the degree of coronary artery stenosis in suspected coronary artery disease (CAD) patients with normal LV ejection fraction and regional wall motion. A total of 164 suspected CAD patients were divided into four groups according to coronary artery angiography. The results showed that global work efficiency (GWE) as the most significant predictor in all MW parameters had the optimal cut-off value of 94.5% for detecting moderate stenosis, and the sensitivity and specificity was 89.7% and 85.8%, respectively. A cut-off value of 94.0% for GWE was the most significant predictor of severe stenosis, and the sensitivity and specificity was 81.4% and 76.1%, respectively. In conclusion, LV global MW is a sensitive tool in detecting the degree of coronary artery stenosis and a potential valuable method to provide early diagnosis for CAD patients.

Targeted galectin-7 inhibition with ultrasound microbubble targeted gene therapy as a sole therapy to prevent acute rejection following heart transplantation in a Rodent model.

BACKGROUND: Despite significant advances in transplantation, acute cellular rejection (AR) remains a major obstacle that is most prevalent in the first months post heart transplantation (HT). Current treatments require high doses of immunosuppressive drugs followed by maintenance therapies that have systemic side effects including early infection. In this study, we attempted to prevent AR with a myocardial-targeted galectin-7-siRNA delivery method using cationic microbubbles (CMBs) combined with ultrasound targeted microbubble destruction (UTMD) to create local immunosuppression in a rat abdominal heterotopic heart transplantation acute rejection model. METHODS AND RESULTS: Galectin-7-siRNA (siGal-7) bound to CMBs were synthesized and effective ultrasound-targeted delivery of siGal-7 into target cells confirmed in vitro. Based on these observations, three transplant rat models were tested：①isograft (ISO); ② Allograft (ALLO) +UTMD; and ③ALLO + PBS. UTMD treatments were administered at 1, 3, 5, 7 days after HT. Galectin 7 expression was reduced by 50% compared to ALLO + PBS (p < 0.005), and this was associated with significant reductions in both galectin 7 and Interleukin-2 protein levels (p < 0.001). The ALLO + UTMD group had Grade II or less inflammatory infiltration and myocyte damage in 11/12 rats using International Society For Heart and Lung Transplantation grading, compared to 0/12 rats with this grading in the ALLO + PBS group at 10 days post HT (p < 0.001). CONCLUSIONS: Ultrasound-targeted galectin-7-siRNA knockdown with UTMD can prevent acute cellular rejection in the early period after allograft heart transplantation without the need for systemic immunosuppression. KEY WORDS: Microbubble, Acute Rejection, Heart Transplantation, Galectin-7, RNA.

miR-205-5p inhibits cell migration and invasion in prostatic carcinoma by targeting ZEB1.

Many studies have demonstrated that miRNAs have influence on tumorigenesis and progression of human cancers, including invasion and migration. Thus, the role of miR-205/ZEB1 axis for the migration and invasion of prostate cancer cells was explored in the present study. The miR-205-5p and zinc finger E-box binding homeobox 1 (ZEB1) mRNA expression levels were observed in prostate cancer tissues or cell lines via reverse transcription-quantitative PCR (RT-qPCR), and the protein level of ZEB1 was measured by western blotting. Dual-Luciferase Reporter Assay was used to verify the relationship between miR-205-5p and ZEB1. In addition, cell migration and invasion was measured by Transwell assay. The results revealed that, compared with the control, downregulation of miR-205-5p was detected in prostate cancer tissues and cell lines, and miR-205-5p overexpression was found to inhibit cell migration and invasion. Moreover, miR-205-5p was confirmed to directly target ZEB1 in prostate cancer. Importantly, ZEB1 was identified to weaken the inhibitory effect of miR-205-5p in prostate cancer. In conclusion, miR-205-5p inhibited cell migration and invasion in prostatic carcinoma by targeting ZEB1 and miR-205-5p/ZEB1 axis shows potential to be developed in therapeutic strategies for prostate cancer.

In vivo degradation and neovascularization of silk fibroin implants monitored by multiple modes ultrasound for surgical applications.

BACKGROUND: In this paper we aimed to investigate the neovascularization and biodegradation of the silk fibroin in vivo using multiple modes ultrasound, including two-dimensional, three-dimensional and contrast-enhanced ultrasound by quantifying the echo intensity, volume and contrast enhancement of the silk fibroin implants. METHOD: A total of 56 male Wistar rats were randomly divided into two groups and 4%(w/v) silk hydrogels were injected subcutaneously at hind limb or upper back of the rats respectively to compare the biodegradation rate in different sites of the body. The implants were observed at day 0, 4, 8, 12, 16, 18, 20 with multiple modes ultrasound. RESULTS: The echo intensity of silk fibroin implants increased and the volume decreased gradually, and complete degradation was confirmed 18 and 20 days after subcutaneous implantation at the upper back and at the hind limb respectively. This demonstrated that the silk fibroin embedded in the upper back degraded slightly faster than that in the hind limb. Additionally, the neovascularization revealed by the contrast enhancement values of CEUS showed that there was a relatively low enhancement (< 5 dB) during day 4 to day 16, followed by moderate enhancement at day 18 (5-20 dB), and a significant enhancement at day 20 (> 40 dB). CONCLUSION: This study suggests that multiple modes ultrasound imaging could be an ideal method to evaluate the degradation and neovascularization of biomaterial implants in vivo for surgical applications.

In situ ultrasound imaging of silk hydrogel degradation and neovascularization.

Ultrasound (US) is a useful technique to monitor morphological and functional changes of biomaterial implants without sacrificing the animal. Contrast-enhanced ultrasound (CEUS) along with two-dimensional (2D) US were used to characterize the biodegradation and neovascularization of silk protein (8 wt%) hydrogel implants in rats. Cylinder-shaped silk hydrogel plugs were implanted into the space between the hind limb thigh muscles in Wistar rats (n = 6). The increase of echogenicity in 2D US revealed tissue-ingrowth-accompanied gel degradation over 18 weeks. The shape and size of the implanted gels remained qualitatively unchanged until week 15, as confirmed by Bland and Altman analysis and visualization of retrieved samples. Using CEUS, neovascularization was monitored by the presence of microbubbles in the gel area, and the dynamic vascularization process was indicated by the contrast enhancement values, which showed a relatively low level (< 5 dB) during weeks 1-8 and significantly increased levels (around 20 dB at week 15 and > 35 dB at week 18), suggesting that major vascularization had occurred in the gel implants by this time point. Histological and scanning electron microscopic analysis of explants revealed time-dependent increases in the pore size of the gel matrix, the presence of endothelial and red blood cells and the number of blood vessels in the gel implants, indicating that degradation and vascularization did occur in silk gel implants during the time period. The present study demonstrates the use of US imaging for monitoring of in vivo degradation and vascularization of silk implants in a non-destructive way. Copyright © 2015 John Wiley & Sons, Ltd.

Novel cell-penetrating peptide-loaded nanobubbles synergized with ultrasound irradiation enhance EGFR siRNA delivery for triple negative Breast cancer therapy.

The lack of safe and effective gene delivery strategies remains a bottleneck for cancer gene therapy. Here, we describe the synthesis, characterization, and application of cell-penetrating peptide (CPP)-loaded nanobubbles (NBs), which are characterized by their safety, strong penetrating power and high gene loading capability for gene delivery. An epidermal growth factor receptor (EGFR)-targeted small interfering RNA (siEGFR) was transfected into triple negative breast cancer (TNBC) cells via prepared CPP-NBs synergized with ultrasound-targeted microbubble destruction (UTMD) technology. Fluorescence microscopy showed that siEGFR and CPP were loaded on the shells of the NBs. The transfection efficiency and cell proliferation levels were evaluated by FACS and MTT assays, respectively. In addition, in vivo experiments showed that the expression of EGFR mRNA and protein could be efficiently downregulated and that the growth of a xenograft tumor derived from TNBC cells could be inhibited. Our results indicate that CPP-NBs carrying siEGFR could potentially be used as a promising non-viral gene vector that can be synergized with UTMD technology for efficient TNBC therapy.

Complexation of chlorpropham with hydroxypropyl-ß-cyclodextrin and its application in potato sprout inhibition.

The effect of hydroxypropyl-ß-cyclodextrin (HPßCD) on the improvement of chlorpropham (CIPC) as a potato sprout inhibitor was investigated. The formation of complex was confirmed by FT-IR spectra, thermoanalysis, (1)H NMR and ROESY. The stoichiometry and stability constant were determined by Job's plot and phase solubility studies, respectively. The inclusion complex CIPC·HPßCD has exhibited different properties from CIPC. The obtained inclusion complex was found to significantly improve the water solubility, thermal stability and dissolution rate of CIPC. In addition, the complex displayed a better effect on sprout inhibition.