The acoustic properties of ultrasound and the interaction of biomaterial and cavitation are analyzed. The relation between ultrasonic parameters and sonication is indicated. Our research revealed that different sonication aims must well match with different acoustic properties for optimizing the sonication technology. Based on the theory of wave superposition, a method for enhancement of ultrasonic intensity in wide dimension is introduced. A large scale powerful polyhedral acoustic field is built according to the research above. The rationality and effectiveness of the method are demonstrated through examination.
Acoustics ; Biocompatible Materials ; Humans ; Sonication ; Ultrasonics

BACKGROUND: The diagnosis of catheter-related bloodstream infection (CRBSI) should demonstrate catheter colonization of the same organism as the isolate from peripheral blood cultures, by catheter tip culture or by differential time to positivity (DTP) of catheter-drawn blood cultures versus peripheral blood cultures. The purpose of this study was to compare the sonication and the roll-plate methods of catheter tip culture. METHODS: One hundred and sixty-one catheter tips from 122 patients were submitted for catheter tip culture. Distal segments of the catheter were first inoculated using a roll-plate, and then inoculated by sonication. Sonication was performed using a BactoSonic device (Bandelin GmbH, Germany). A total of 1,018 sets of blood cultures from 7 days before to 1 day after catheter removal were analyzed for isolated organisms and DTP. Cutoffs of catheter colonization were > or =15 CFU for the roll-plate method, > or =100 CFU for sonication, and > or =2 h for DTP. RESULTS: Twenty-four catheter tips (14.9%) showed colonization with at least one of the two methods: 21 (13.0%) with the roll-plate method and 22 (13.7%) with sonication. The positivity rates for the two methods showed no significant difference, and the concordance rate for the two methods was 96.9% (k=0.866, P<0.001). Blood culture was positive in 56 episodes in 44 patients, and 14 episodes of CRBSI were diagnosed in 12 patients: 10 by tip culture (two by sonication only) and 8 by DTP. Of the 122 specimens that were negative according to both methods, 4 were from the episodes of CRBSI diagnosed by DTP. CONCLUSION: Roll-plate and sonication methods are comparable in diagnostic sensitivity for catheter colonization. The roll-plate and sonication catheter tip culture methods and DTP are complementary for diagnosis of CRBSI.
Catheters* ; Central Venous Catheters ; Colon ; Diagnosis* ; Humans ; Sonication*

BACKGROUND: Generation of perfluorocarbon-exposed sonicated dextrose albumin (PESDA), the custom-made contrast agent, is performed under certain conditions that have been proposed by its original developer. We doubted whether the known composition and manufacturing method of PESDA is ideal and if there is an optimal method of storing batches of PESDA for a significant time duration. METHODS: PESDA was generated with several different composition of ingredients (5% human serum albumin, 5% dextrose water, and perfluorocarbon (PFC) gas), where various ratios of each were used. Sonication was performed for various durations. After manufacturing, the mean size and concentration of the microbubbles were evaluated by hemocytometer and compared. The generated PESDA was stored for 48 hours under 4 degrees C or -20 degrees C and changes in size and concentration of microbubbles were evaluated and compared. RESULTS: The best concentration of microbubbles was found with a mix ratio of albumin: PFC: dextrose of 1:1:1 and sonication time of 90 sec. The microbubble concentration of the optimal PESDA was not different to that of the conventionally manufactured one (9.47+/-1.70 x 10(8) /mL vs. 8.34+/-0.87 x 10(8) /mL, p>0.05) but the mean microbubble size was significantly smaller (1.22+/-0.31 um vs. 1.66+/-0.32 um, p<0.01). After 48 hours, the concentration of microbubbles was reduced by 34+/-3% (p=NS) and 55+/-0.2% (p<0.05) and the size increased by 77+/-25% and 108+/-41% (p=NS in both) in the 4 degrees C -stored and -20 degrees C -stored PESDA, respectively. CONCLUSION: The optimal composition of PESDA ingredients is 1:1:1 for albumin, PFC, and dextrose water, and the best duration of sonication is 90 seconds. Refrigeration under 4 degrees C may be the best way for storage of PESDA for 48 hours.
Echocardiography ; Glucose* ; Humans ; Microbubbles ; Refrigeration ; Serum Albumin ; Sonication ; Water

The method of cell lysate preparation of M. leprae is an important technique in the study of leprosy. This report describes the optimization of method for cell lysate preparation of M. leprae obtained from infected nude mouse. After M. leprae isolated from nude mouse foot-pad was disrupted by sonication, it was centrifuged and then whole lysate was prepared. With this method it was possible to isolate 0.3 mg whole cell lysate using 20 mg of M. leprae. By SDS-PAGE and Coomassie blue staining, the number of protein in M. leprae is less than that of other bacteria, for example, E. coli and M. smegmatis. It is likely that this is due to the small genome size. This work will contribute to the analysis of new protein antigen of M. leprae and the basic study for the development of vaccine in leprosy.
Animals ; Bacteria ; Electrophoresis, Polyacrylamide Gel ; Genome Size ; Leprosy ; Mice ; Mice, Nude* ; Sonication

OBJECTIVETo observe the effect of ultrasound stimulation at the acupoint Guanyuan (CV 4) on follicular development in menopausal rats.

METHODSMenopausal female SD rats were selected by vaginal smear examinations. The rats were subjected to ultrasound stimulation at the acupoint Guanyuan with the output power of 0.1 W, working frequency of 9 MHz, and focal length of 4.5-5 mm. Electrochemiluminescence immunoassay was used to detect the serum estrogen levels of the menopausal rats. The changes in the ovarian tissue histology and the follicle number were observed.

RESULTSCompared with the control group, a 10-day ultrasound stimulation for 10 and 5 min daily at Guanyuan significantly increased the serum estrogen levels and the numbers of primary and secondary follicles (P<0.05) and reduced the number of atretic follicles in the menopausal rats (P<0.05).

CONCLUSIONUltrasound stimulation at the acupoint Guanyuan can increase the estrogen secretion function and promote the development of follicles in menopausal rats.

Acupuncture Points ; Animals ; Estrogens ; blood ; Female ; Menopause ; Ovarian Follicle ; growth & development ; Rats ; Rats, Sprague-Dawley ; Sonication

OBJECTIVES: The present study was designed to systematically characterize the denaturation and the renaturation of double stranded DNA (dsDNA), which is suitable for DNA hybridization. METHODS: A series of physical and chemical denaturation methods were implemented on well-defined 86-bp dsDNA fragment. The degree of each denaturation was measured and the most suitable denaturation method was determined. DNA renaturation tendency was also investigated for the suggested denaturation method. RESULTS: Heating, beads mill, and sonication bath did not show any denaturation for 30 minutes. However probe sonication fully denatured DNA in 5 minutes. 1 mol/L sodium hydroxide (alkaline treatment) and 60% dimethyl sulfoxide (DMSO) treatment fully denatured DNA in 2-5 minutes. CONCLUSIONS: Among all the physical methods applied, the direct probe sonication was the most effective way to denature the DNA fragments. Among chemical methods, 60% DMSO was the most adequate denaturation method since it does not cause full renaturation during DNA hybridization.
Baths ; Dimethyl Sulfoxide ; DNA* ; Heating ; Hot Temperature ; Nucleic Acid Denaturation ; Sodium Hydroxide ; Sonication

BACKGROUNDTo evaluate the influence ultrasonic processing on the aggregation of PrP(Sc) in the brain extracts prepared from the scrapie-infected hamsters, and to seek for the way to prepare lower molecular PrP(Sc) polymer.

METHODSThe extracts of infected brains were prepared with a lysis solution, and treated with ultrasonics at various conditions during the different phases. The distribution and aggregation state of PrP(Sc) were analyzed by proteinase K treated. Western blot, and afterwards, quantitatively calculated with a commercially supplied software Image Totaltech.

RESULTSThe amount of PrP(Sc) in the supernatant of brain homogenates was 1.29-to 1.58-fold increased with appropriate sonication (15 s for 30 times). At the same conditions of ultrasound, the PrP amount in the supernatant prepared from the scrapie-infected hamster brain was significantly increased, whereas that prepared from healthy animal used as normal control showed little change. Comparative analyses of PrP(Sc) pellets prepared by high-speed centrifugation revealed that about 90% PrP(Sc) released into supernatant after ultrasound processing.

CONCLUSIONAppropriate sonication of homogenate of scrapie-infected brain increases the extracted amount of PrP(Sc), being favorable to laboratory diagnosis. Larger molecular PrP(Sc) aggregates can be crashed by ultrasonic processing, engendering lower molecular PrP(Sc) polymers.

Animals ; Blotting, Western ; Brain Chemistry ; Cricetinae ; Image Processing, Computer-Assisted ; PrPSc Proteins ; analysis ; Scrapie ; metabolism ; Sonication

AIMTo compare sonoporation effect of two phospholipids-based vectors-liposomes and microbubbles on cultured cell membrane.

METHODSA breast cancer cell line SK-BR-3 was exposed to ultrasound alone, 2% or 5% liposome + ultrasound and 2% or 5% microbubble + ultrasound, separately. Immediately after the experiment and 24 h after ultrasound exposure, atomic-force microscopy (AFM) scanning was used to observe the membrane change of SK-BR-3 cells.

RESULTSAfter ultrasound exposure, normal SK-BR-3 cells more or less lost their natural shape, showing elliptic outline with obtuse curved boundary. In groups added with phospholipids-based microbubbles, more obtuse curved boundary of cells was observed. The membrane pores of SK-BR-3 cells had apparent changes after ultrasound exposure. With AFM technique, membrane pores under ultrasound alone or ultrasound with liposomes conditions were enlarged, the diameter of some pores exceeding 1 microm. But all the membrane pores in these conditions returned to normal appearance after 24 hours. In ultrasound with 2% microbubble condition, most membrane pores were about 1 - 3 microm in size and returned to normal appearance after 24 h. In ultrasound with 5% microbubble condition, however, pores of most cell membrane porosity was about 2 - 4 pm and did not totally return to normal appearance after 24 h.

CONCLUSIONAt 2% concentration, phospholipids-based microbubble could enhance ultrasonic sonoporation effect and produce reparable membrane pores on SK-BR-3 cells, which appeared to be a promising vehicle for drug and gene delivery.

Cell Membrane Permeability ; Drug Carriers ; Liposomes ; Microbubbles ; Phospholipids ; chemistry ; Porosity ; Sonication ; instrumentation ; Technology, Pharmaceutical

In this study we deliberated over the principles and methods and then took the noninvasive continuous measurement of blood glucose concentration through the skin of rabbits. The glucose oxidase sensor was made by covalent immobilization. The best making method of sensor and stable working condition were sifted. Ten female and 10 male adult white rabbits were allocated into the groups of the ante-ultrasound and post-ultrasound, the injection of glucose, and the high and low frequency ultrasounds. After the skin surface was treated by high or low frenquency ultrasound for 5 minutes on the rabbits, obvious changes (P < 0.01) of post-ultrasound and post-injection of glucose were observed by means of glucose oxidase sensor and microcurrent apparatus. After application of ultrasound to the skin of rabbits, the penetration of glucose through the rabbit skin increased obviously. The change of microcurrent signal that was exchanged by the glucose sensor correlated positively with the concentration of glucose of rabbit body. The blood glucose can be tested by the glucose sensor on the skin surface of living animal.
Animals ; Biosensing Techniques ; Blood Glucose ; analysis ; Female ; Glucose Oxidase ; Male ; Rabbits ; Skin ; radiation effects ; Sonication

OBJECTIVETo prepare solid lipid nanoparticles (SLN) loaded tetrandrine (TET) extracted from traditional Chinese medicine with ultrasonication and high pressure homogenization, and to compare the physicochemical characteristics of the particles produced by the two methods.

METHODSTET was incorporated into SLN by ultrasonication and high pressure homogenization separately. Transmission electron microscopy was employed to study the shape. Particle characterization system and Zeta potential analyzer were used to study the diameter and Zeta potential of SLN in suspension. The entrapment efficiency was determined with the high-performance liquid chromatography. The stability of SLN was also studied.

RESULTSTET-SLNs prepared by these two methods were sheet-shaped and irregular, but the SLNs prepared by high pressure homogenization were smaller. The mean diameter of SLN prepared by ultrasonication was (92 +/- 6) nm with Zeta potential of (-21.11 +/- 2.12) mV in distilled water, and the mean entrapment efficiency was 95.27%. The mean diameter of TET-SLN prepared by high pressure homogenization was (47 +/- 3) nm with Zeta potential of (-32.99 +/- 2.54) mV, and up to 97.82% of TET was incorporated. The diameter of SLN prepared by high pressure homogenization and ultrasonication were (52 +/- 5) nm and (168 +/- 12) nm after 90 days of storage at room temperature.

CONCLUSIONCompared with ultrasonication, high pressure homogenization is a better method to prepare TET-SLN, which is smaller, steadier and highly incorporated.

Alkaloids ; chemistry ; Benzylisoquinolines ; chemistry ; Drug Compounding ; methods ; Lipids ; chemistry ; Nanoparticles ; Sonication