Ultrasound-mediated structural changes in cells revealed by FTIR spectroscopy: a contribution to the optimization of gene and drug delivery

Ultrasound effects on biological samples are gaining a growing interest concerning in particular, the intracellular delivery of drugs and genes in a safe and in a efficient way. Future progress in this field will require a better understanding of how ultrasound and acoustic cavitation affect the biological system properties. The morphological changes of cells due to ultrasound (US) exposure have been extensively studied, while little attention has been given to the cells structural changes. We have exposed two different cell lines to 1 MHz frequency ultrasound currently used in therapy, Jurkat T-lymphocytes and NIH-3T3 fibroblasts, both employed as models respectively in the apoptosis and in the gene therapy studies. The Fourier Transform Infrared (FTIR) Spectroscopy was used as probe to reveal the structural changes in particular molecular groups belonging to the main biological systems. The genotoxic damage of cells exposed to ultrasound was ascertained by the Cytokinesis-Block Micronucleus (CBMN) assay. The FTIR spectroscopy results, combined with multivariate statistical analysis, regarding all cellular components (lipids, proteins, nucleic acids) of the two cell lines, show that Jurkat cells are more sensitive to therapeutic ultrasound in the lipid and protein regions, whereas the NIH-3T3 cells are more sensitive in the nucleic acids region; a meaningful genotoxic effect is present in both cell lines only for long sonication times while in the Jurkat cells also a significant cytotoxic effect is revealed for long times of exposure to ultrasound.     

Aptamer-conjugated nanobubbles for targeted ultrasound molecular imaging

Targeted ultrasound contrast agents can be prepared by some specific bioconjugation techniques. The biotin-avidin complex is an extremely useful noncovalent binding system, but the system might induce immunogenic side effects in human bodies. Previous proposed covalently conjugated systems suffered from low conjugation efficiency and complex procedures. In this study, we propose a covalently conjugated nanobubble coupling with nucleic acid ligands, aptamers, for providing a higher specific affinity for ultrasound targeting studies. The sgc8c aptamer was linked with nanobubbles through thiol-maleimide coupling chemistry for specific targeting to CCRF-CEM cells. Further improvements to reduce the required time and avoid the degradation of nanobubbles during conjugation procedures were also made. Several investigations were used to discuss the performance and consistency of the prepared nanobubbles, such as size distribution, conjugation efficiency analysis, and flow cytometry assay. Further, we applied our conjugated nanobubbles to ex vivo ultrasound targeted imaging and compared the resulting images with optical images. The results indicated the availability of aptamer-conjugated nanobubbles in targeted ultrasound imaging and the practicability of using a highly sensitive ultrasound system in noninvasive biological research.     

Influence of ultrasonic stimulation on the growth and proliferation of Oryza sativa Nipponbare callus cells

Ultrasound acts as an alternative stress on cells or tissues. In this study it is aimed to investigate the effect of ultrasonic stimulation on the growth and proliferation of Oryza sativa Nipponbare cells (rice callus) in suspension culture. After the samples were stimulated by ultrasound at 28 kHz, we measured their growth and proliferation by using a colorimetric MTT ((3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay as well as fresh weights of the cells. Growth curves were obtained by fresh weights in the suspension culture after ultrasonic agitation for different time from 2 to 120 s. In MTT method, the optical density was determined at 570 nm in the cell suspension on 10 days after the ultrasonic agitation. Up to 5 s agitation OD₅₇₀ increased; it decreased for more prolonged stimulation. We found that ultrasonic stimulation could promote the growth and proliferation of O. sativa Nipponbare cells in suspension culture with the optimal stimulation of 5 s, while with longer agitation, its growth and proliferation was inhibited. The mechanism may be that the ultrasound activated or destroyed the cellular structure, such as cell membrane, cytoskeleton and mitochondria in which many enzymes and ion channels are affected. In addition, the enhancement of cell wall and cell membrane fluidity might be one of the factors to promote the cell growth in 5-s ultrasonic stimulation.     

经阴道超声和经腹部超声测量瘢痕妊娠的瘢痕厚度与实际厚度的相关性分析

采用阴道超声和腹部超声检测瘢痕妊娠患者瘢痕厚度,分析两种超声方式检测结果与患者实际厚度的相关性。选取本院收治的424例剖宫产后瘢痕子宫妊娠患者进行研究,分析阴道和腹部超声检测结果和手术观察结果间的相关性。检查发现,阴道超声检出率,以及与手术数据的相关系数,均明显优于腹部超声,证明阴道超声与手术观察结果的相关性更强,P<0.05,差别具有统计学意义;经Logistic回归分析结果显示,阴道超声检测的瘢痕厚度与手术观察结果的符合度更高,P<0.05,差别有统计学意义。本研究结果证明阴道超声和腹部超声相比,前者的检测结果与手术观察结果更为相符,能够准确显示出患者子宫前壁下段有无瘢痕问题,提升确诊率。     

超声活化的CuBr~2 / Al~2O~3 对萘的溴化

本文用超声及非超声的方法制备了以氧化铝为载体的溴化铜, 并研究了它们对萘的溴化反应.     

有机化合物血卟啉及其衍生物被物理因素--超声激活机理研究

利用1,3-二苯基异苯并呋喃(DPBF)作为单线态氧捕获剂,研究了超声激活血卟啉的机理,通过用紫外-可见分光光度计测量了超声辐照配制好的血卟啉和DPBF溶液后的DPBF相对消耗量,表明了单线态氧的存在量．实验结果显示了DPBF的消耗量随超声照射时间和强度的增加而增加．从而支持了超声激活血卟啉产生单线态氧的说法．并提出了采用各向同性集光球把声致发光和声场分开的方法,进一步研究了是超声空化产生的荧光,还是高温热点激活血卟啉产生单线态氧．与白光对比结果表明,声致发光虽能使照相底版感光,但不足以激活血卟啉产生单线态氧．     

高频超声联合彩色多普勒超声对甲状腺良/恶性结节的诊断价值

本文探讨了高频超声联合彩色多普勒超声对甲状腺结节良/恶性的诊断价值.选择疑似甲状腺结节患者82例作为研究对象,本研究比较了高频超声和彩色多普勒超声与术后病理结果的差异;绘制了ROC曲线,分析了高频超声联合彩色多普勒超声对甲状腺结节良/恶性的诊断效能.结果发现,病理学检查与高频超声联合彩色多普勒超声检查相比较,差异不具有...     

Mechanism of enhancement of sonochemical-reaction efficiency by pulsed ultrasound

The enhancement of sonochemical-reaction efficiency by pulsed ultrasound at 152 kHz has been studied experimentally through absorbance measurements of triiodide ions from sonochemical oxidation of potassium iodide at different liquid volumes to determine sonochemical efficiency defined by reacted molecules per input ultrasonic energy. The mechanism for enhancement of the reaction efficiency by pulsed ultrasound is discussed using captured images of sonochemiluminescence (SCL), and measured time-resolved signals of the SCL pulses and pressure amplitudes. The high sonochemical-reaction efficiency by pulsed ultrasound, compared with that by continuous-wave ultrasound, is attributed both to the residual pressure amplitude during the pulse-off time and to the spatial enlargement of active reaction sites.     

超声共沉淀法制备纳米结构LaNiO3及其性质

使用超声共沉淀法制备了LaNiO3复合氧化物纳米催化剂,研究了共沉淀过程中超声波对LaNiO3结构性质和催化活性的影响.X射线衍射分析(XRD)、表面吸附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、程序升温还原（TPR）和活性评价等表征.结果表明, 在共沉淀过程中施加超声波辐照,可以使LaNiO3复合氧化物的粒径减小,比表面积增加,表面晶格氧空位增加, 表面吸附氧种增加, 使LaNiO3催化剂的表面氧种活化, 表面氧与体相晶格氧的比例增加, 使LaNiO3催化剂的催化活性增加.探讨了超声波作用的机理.     

Effect of ultrasound on the microstructure of polystyrene in cyclohexane: a synchrotron small-angle X-ray scattering study

Synchrotron small-angle X-ray scattering technique has been used to study the effect of ultrasound on the microstructure of polystyrene (PS) in cyclohexane solutions. The results show that the intramolecular radius of gyration (R _g) decreases with ultrasound, indicating the shrinkage and collapse of PS chains. There is an exponential relationship between R _g and the molecular weight of PS (M _w), and the exponent changes from 0.5 to 0.417, as the ultrasound time is increased. This means that the shape of PS chain changes from random coil to shrunken form. The Kratky plots also confirm the shape transformation of PS chains induced by ultrasound. Moreover, the intermolecular correlation length increases with the ultrasound time, which is indicative of the entanglement of PS chains.     

The effects of ultrasound frequency and power on the activation energy in Si-KOH reaction system

The activation energy is the minimum amount of energy required to initiate a reaction. It is one of the important indexes for appraising a reaction. The chemical reaction rate is closely related to the value of activation energy, and reducing activation energy is propitious to promoting a chemical reaction. In the present paper, the relationship between the activation energy in Si-KOH reaction system and the ultrasound frequency and power has been discussed for the first time. The range of ultrasound frequency and power is 40-100kHz （interval by 20kHz） and 10-50W （interval by 10W）, respectively. The experimental clata indicate that the activation energy decreases with the increasing ultrasound power. Comparing with the activation energy without ultrasound irradiation, the results in our paper indicate that ultrasound irradiation could reduce the activation energy in Si-KOH reaction system and increase the reaction rate.     

经直肠超声联合前列腺特异抗原密度诊断前列腺癌的临床应用价值研究

为探讨经直肠超声与前列腺特异抗原密度(PSAD)联合检查诊断前列腺癌的临床应用价值,选取本院2013年9月~2018年9月期间内接收的97例血清前列腺特异性抗原(PSA)患者实施研究。所有患者均行经直肠超声与前列腺特异抗原密度(PSAD)联合检查,并与手术病理结果进行对比。观察PSAD检查结果,分析经直肠超声与PSAD联合检查的诊断符合率,并对比病理结果与经直肠超声和PSAD联合检查的准确率、灵敏性、特异性情况,分析前列腺癌患者经直肠超声检查的影像学特征及内部回声情况。与病理结果对比,经直肠超声与PSAD联合检查对前列腺癌、移行细胞癌、黏液腺癌检出率均稍低(P>0.05);经直肠超声与PSAD联合检查的准确率、灵敏性、特异性较病理检查均稍低(P>0.05)。经直肠超声检查后根据图像表现可将疾病分为弥漫性、结节型、无结节型3型,不同类型的影像学特征及内部回声情况表现不同,表明经直肠超声与PSAD联合诊断前列腺癌准确性较高,并且可清晰地对不同疾病类型的内部回声作出反映,临床实用价值较高,值得加以推广。     

超声弹性成像联合超声造影在鉴别原发性及转移性肝癌中的应用

为探讨超声弹性成像联合超声造影在鉴别原发性及转移性肝癌中的应用价值，选择2016年12月至2018年12月期间本院消化外科住院部收治的肝癌患者160例作为研究对象，根据病理组织学检查结果将患者分为原发组和转移组，各80例，两组进行超声弹性成像和超声造影检查，分析单项和两者联合检查对原发性及转移性肝癌的鉴别诊断效能。结果显示，原发组超声弹性成像评分（3.41±0.85）分，明显高于转移组的（1.52±0.62）分，两组比较差异具有统计学意义，P<0.05。与转移组相比较，原发组造影峰值时间明显延长，造影始增时间明显缩短，造影峰值增强速率明显降低，两组比较差异具有统计学意义（P<0.05）。两者联合检查对原发性及转移性肝癌的鉴别诊断灵敏度、特异度、阳性预测值、阴性预测值、准确度高于超声弹性成像或超声造影单项检查，漏诊率和误诊率低于超声弹性成像或超声造影单项检查，两者联合检查对原发性及转移性肝癌的鉴别诊断准确度明显高于超声造影单项检查，P<0.05。说明超声弹性成像联合超声造影有利于明显提高原发性及转移性肝癌的鉴别诊断准确度，值得临床推广应用。     

The Application of Ultrasound in the Enzymatic Hydrolysis of Switchgrass

In a series of experiments, untreated and ammonium hydroxide pretreated Klenow lowland variety switchgrasses are converted to reducing sugars using low-frequency (20 kHz) ultrasound and commercially available cellulase enzyme. Results from experiments using untreated and pretreated switchgrasses with and without ultrasound are presented and discussed. In untreated switchgrass experiments, the combination of ultrasound and enzymes resulted in an increase of 7.5% in reducing sugars compared to experiments using just enzymes. In experiments using ammonium hydroxide pretreated switchgrass, the combination of ultrasound and enzymes resulted in an increase of 9.3% in reducing sugars compared to experiments using just enzymes. Experimental evidence indicates that there is a synergistic effect from the combination of ultrasound and enzymes which lowers the diffusion-limiting barrier to enzyme/substrate binding and results in an increase in reaction rate. Scanning electron microscopic images provide evidence that ultrasound-induced pitting increases substrate surface area and affects reaction rate and yield.     

超声功率对石灰乳活性影响研究

为获得高活性度的石灰乳,在石灰乳化过程引入超声作用,分别采用沉降实验、粒度分析和表观形态观察、中和反应活性实验对超声作用后石灰乳的性质进行了分析,比较机械搅拌和不同超声功率作用下石灰乳的分散稳定性、中和反应活性及粒度分布情况,以考察超声作用对石灰乳化过程和石灰乳性质的影响。结果表明:与机械搅拌相比,在一定功率范围内,超声作用可降低石灰乳的沉降速率,提高其分散稳定性;减小石灰乳体系中未溶解Ca(OH)2乳颗粒的粒径,并缩小其粒径的分布范围,抑制石灰乳结块的产生;超声作用还增加了Ca(OH)2颗粒的比表面积和溶解速度,进而提高石灰乳的中和反应活性。     

Combination of ultrasound and discarded tire rubber: removal of Cr(III) from aqueous solution

Ground discarded tire rubber is an interesting and inexpensive medium for the sorption of toxic metals, including chromium, from water. The batch sorption tests were conducted to investigate the sorption capacity of Cr(III) from aqueous solution by ground tire in the presence and absence of ultrasound. The research parameters included ultrasonic waves, solution temperature, aqueous chromium concentration, particle size of the ground tire, contact time, and others. The Langmuir model was applied to the sorption equilibrium to determine the maximum metal sorption capacity in the presence and absence of ultrasound. The Langmuir constants were also obtained from the isotherms under different conditions. The results indicated that the tire rubber was a more efficient sorbent for the removal of chromium in the presence of ultrasound. Because there are several stages in the sorption process, it is important to find out which step or steps control the rate of sorption. According to the results, the internal porous diffusion is the rate-controlling step. The diffusion coefficient of Cr(III) in ground tire rubber in the presence of ultrasound was about two times greater than that in the absence of ultrasound. The effect of ultrasound on the sorption process could be explained by the thermal and nonthermal properties of acoustic cavitation.     

超声技术在查尔酮合成中的应用研究

查尔酮是重要的有机合成中间体。报道了在KF－Al2O3的催化下，应用超声波 技术合成查尔酮类化合物的方法，并研究了超声辐射功率、辐射时间对产物产率的 影响，得出了最佳的合成反应条件。控制超声功率为250W，反应30min，查尔酮（ 除化合物3b)的产率达95％以上。结果表明该方法操作简单、条件温和、反应速度 快、产率高。     

Effect of ultrasound frequency on pulsed sonolytic degradation of octylbenzene sulfonic acid

It has been shown that pulsed ultrasound can influence the amount of surfactant that can adsorb to and decompose at the surface of cavitation bubbles. However, the effect of ultrasound frequency on this process has not been considered. The current study investigates the effect of ultrasound frequency on the pulsed sonolytic degradation of octyl benzenesulfonate (OBS). Furthermore, the effect of pulsing and ultrasound frequency on the rate of *OH radical formation was determined. OBS degradation rates were compared to the rates of *OH radical formation. In this way, conclusions were made regarding the relative importance of accumulation of OBS at cavitation bubble surfaces versus sonochemical activity to the sonochemical decomposition of OBS under different conditions of sonolysis. Comparisons of the data in this way indicate that sonolytic degradation of OBS depends on both the sonochemical activity (i.e., *OH yield) and the accumulation of OBS on cavitation bubble surfaces. However, under a certain set of pulsing and ultrasound frequency exposure conditions, enhanced accumulation of OBS at the gas/solution interface of cavitation bubbles is the sole mechanism of enhanced degradation due to pulsing. On the basis of this finding, conclusions on how pulsing at various ultrasound frequencies affects cavitation bubbles were made.     

Mist separation and sonochemiluminescence under pulsed ultrasound

Differences in the amount of water-mist separation and the intensity of luminol chemiluminescence for pulsed and continuous-wave (CW) ultrasound at 135 kHz have been investigated. The amount of mist generated is estimated using the cooling rate of a copper plate sprayed with the mist. For pulsed operation with an appropriate duty cycle, the cooling rate and the cooling rate per input power to the transducer are higher by 4 and 12 times compared to CW operation, respectively. This is due to the amplitude of the pulsed ultrasound being higher than that for CW ultrasound. Relatively low power pulsed operation can successfully produce both a higher sonochemiluminescence (SCL) intensity and cooling rate than those for CW ultrasound. The sonochemical reaction for pulsed ultrasound occurs at the same input power threshold as that for mist separation, whereas for CW ultrasound, the former threshold is lower than the latter. A higher number of large bubbles is produced with CW ultrasound than that with pulsed ultrasound. To achieve a sound pressure amplitude sufficient for mist separation near the surface of a liquid, it is necessary to expel these bubbles by changing the sound field from resonant standing waves to progressive waves that give rise to capillary waves on the liquid surface.     

颈动脉超声联合CT和血清miR-124、miR-155对颈动脉狭窄患者继发性脑梗的风险预测价值

本文探讨了颈动脉超声检查联合CT和血清微小RNA-124(miR-124)、微小RNA-155(miR-155)对颈动脉狭窄患者继发性脑梗的风险预测价值。以43例颈动脉狭窄患者为颈动脉狭窄组,正常志愿者43例为正常组,用RT-PCR法检测miR-124、miR-155表达,采用颈动脉超声检查颈动脉狭窄,采用CT检查颈部血管。结果显示,与正常组相比,颈动脉狭窄组miR-124、miR-155表达升高(P<0.05)。与超声、CT检查相比,超声检查联合CT检查颈动脉狭窄准确率、诊断价值较高(P<0.05)。本研究认为,颈动脉超声、CT、miR-124、miR-155对颈动脉狭窄的诊断价值较高,且可用于预测继发性脑梗的风险,预测价值较为理想。