Sonication Protocol Research Articles

Thermal ablation of soft tissue by a single shock wave sonication of discrete foci within the given volume

New protocols have been developed for shockwave irradiation of soft tissue volumes using trajectories uniformly filled within the given shape by discrete foci, while pulsed millisecond sonication immediately formed a single ablation. The influence of the initial peak power with the same time-average power, the interfocus distance and the geometry of the external contour of the trajectory on the shape, volume and ablation rate was analyzed. The most advantageous is the saturation mode using a trajectory with an interfocus step 1.5 times greater than the transverse size of a single lesion. To obtain volumes of thermal ablation on the order of cubic centimeters, layer-by-layer sonication protocols are proposed, which allow to 2.5 times greater thermal ablation rate compared with protocols used in clinical practice. The advantage of the proposed shockwave protocols is the possibility of obtaining localized and predictable thermal damage without accompanying MRI monitoring.

BIOLOGICAL PROPERTIES OF ZnO PHYTONANOPARTICLES OBTAINED FROM Annona muricata L. FRUIT PULP FOR POSSIBLE CO-ADMINISTRATION WITH PROBIOTICS STRAINS

Phytonanotechnology represents a new approach that uses plant extracts to synthesize metal oxide nanoparticles with higher biocompatibility. Recently, the production of ZnO phytonanoparticles (ZnO PTNPs) for food fortification has gained attention due to their lower risk and outstanding properties. Inclusion of ZnO PTNPs might have some effects as antimicrobial properties against pathogens strains, however, could result in challenges when intended to add probiotics in a nanofortified food matrix. For this reason, the co-administration of ZnO PTNPs with probiotics represents a new scenario for the development of modern functional food. This study aimed to evaluate the biological properties including the antioxidant activity, cytotoxicity, stability during gastrointestinal conditions, and the biological effect on the viability of a probiotic strain of ZnO phytonanoparticles obtained from soursop (Annona muricata L.) pulp for possible co-administration in food applications. The synthesis resulted in the formation of polydisperse ZnO nanowires with thicknesses ranging from 82 to167 nm and ζ potential values + 27.5 mV and +41.8, before and after sonication and stabilization protocol. ZnO PTNPs exhibited an improved antioxidant activity (IC50 = 6.14 mg/mL) compared with the ethanolic extract of Annona muricata L. Non-hemolytic activity in human erythrocytes was evidenced, whereas the interaction between ZnO PTNPs and Lactiplantibacillus fabifermentans BAL-27-ITTG allows the preservation of adequate viable counts of the probiotic microorganism (>1.2X109 UFC/mL), suggesting biocompatibility. Moreover, ZnO PTNPs were shown to be highly stable in stomachal and intestinal conditions with maximum rates of dissolution of 20% and 12%, respectively. Finally, it was confirmed a contribution of 45% of zinc for every dose of ZnO PTNPs used. The present study offers a promising path for the production of functional phytonanoparticles and suggests further investigation for future applications in food matrices.

Minimum and early high-energy sonication protocol of MR-guided focused ultrasound thalamotomy for low-skull density ratio patients with essential tremor and Parkinson's disease.

MR-guided focused ultrasound (MRgFUS) thalamotomy is an incisionless neurosurgical treatment for patients with medically refractory essential tremor and tremor-dominant Parkinson's disease. A low skull density ratio (SDR) < 0.40 is a known risk factor for treatment failure. The aim of this study was to identify useful sonication strategies for patients with a low SDR < 0.40 by modifying the standard sonication protocol using maximum high-energy sonication while minimizing the number of sonications. The authors retrospectively analyzed the effects of modified MRgFUS sonication on low-SDR tremor patients. All patients underwent head CT scans to calculate their SDR. The SDR threshold for MRgFUS thalamotomy was 0.35. The patients in the early series underwent the standard sonication protocol targeting the ventral intermediate nucleus contralateral to the treated hand side. The patients with a low SDR < 0.40 in the late series underwent a modified sonication protocol, in which the number of alignment sonications was minimized and high-energy treatment sonication (> 36,000 J) was used. The authors evaluated the lesion volume the following day and tremor improvement and adverse events 3 and 12 months after the procedure. The sonication patterns between low-SDR patients treated using different sonication protocols were examined using Fisher's exact test. ANOVA was used to examine the lesion volume and tremor improvement in high- and low-SDR patients treated using different sonication protocols. Among 41 patients with an SDR < 0.40, 14 underwent standard sonication and 27 underwent modified sonication. Fewer alignment sonications and high-energy treatment sonications were used in the modified sonication group compared with the standard group (p < 0.001). The duration of modified sonication was significantly shorter than that of standard sonication (p < 0.001). The lesion volume and tremor improvement significantly differed among the high- and low-SDR groups with different sonication protocols (p < 0.001). Low-SDR patients treated using modified sonication protocols had comparable lesion volume and tremor improvement to the high-SDR group. The modified sonication protocol did not significantly increase adverse intraprocedural and postprocedural events. Minimizing alignment sonications and applying high-energy sonication in early treatment help to create an optimal lesion volume and control tremor in low-SDR patients.

Sonication protocols and their contributions to the microbiological diagnosis of implant-associated infections: a review of the current scenario.

Addressing the existing problem in the microbiological diagnosis of infections associated with implants and the current debate about the real power of precision of sonicated fluid culture (SFC), the objective of this review is to describe the methodology and analyze and compare the results obtained in current studies on the subject. Furthermore, the present study also discusses and suggests the best parameters for performing sonication. A search was carried out for recent studies in the literature (2019-2023) that addressed this research topic. As a result, different sonication protocols were adopted in the studies analyzed, as expected, and consequently, there was significant variability between the results obtained regarding the sensitivity and specificity of the technique in relation to the traditional culture method (periprosthetic tissue culture - PTC). Coagulase-negative Staphylococcus (CoNS) and Staphylococcus aureus were identified as the main etiological agents by SFC and PTC, with SFC being important for the identification of pathogens of low virulence that are difficult to detect. Compared to chemical biofilm displacement methods, EDTA and DTT, SFC also produced variable results. In this context, this review provided an overview of the most current scenarios on the topic and theoretical support to improve sonication performance, especially with regard to sensitivity and specificity, by scoring the best parameters from various aspects, including sample collection, storage conditions, cultivation methods, microorganism identification techniques (both phenotypic and molecular) and the cutoff point for colony forming unit (CFU) counts. This study demonstrated the need for standardization of the technique and provided a theoretical basis for a sonication protocol that aims to achieve the highest levels of sensitivity and specificity for the reliable microbiological diagnosis of infections associated with implants and prosthetic devices, such as prosthetic joint infections (PJIs). However, practical application and additional complementary studies are still needed.

Modeling the Osteogenic Potential of Decellularized Human Bone Particles by Tuning their Size Distribution Through a Sonic Microfragmentation Approach

AbstractHuman decellularized bone fragments are commonly used in clinics to perform allograft surgeries. To reduce the immunological response in the recipient and ensure their safety, these fragments underwent decellularization, a procedure that greatly reduces their osteogenicity (the ability to induce differentiation into osteoblast). In this work, by the introduction of an ultrasonication step to fragment the human bone, the size distribution of the resulting demineralize bone particles can be controlled, tuning their osteogenic potential. The sonication protocol is optimized by a response surface method, using 12 different sonication protocols, allowing to model the relationship between the sonication parameters and the outcoming particles properties in terms of dimensions, physical/chemical properties, and biological activity. The size distribution is extrapolated by a deep learning image segmentation while the structure is characterized by infrared and thermal analysis. The particles are combined with methacrylated silk gel to test in vitro their biological response on adipose‐derived stromal cells. The ultrasonication fragmented the bone particles, revealing their internal organic matrix as proved by secondary electron microscopy and confocal microscopy. An inverse linear correlation is found between the particles’ sizes and their osteogenic activity, thus proving the efficacy of the proposed ultrasonication treatment in tuning the biological response.

Complex Dependence of Escherichia coli-based Cell-Free Expression on Sonication Energy During Lysis.

Cell lysis─by sonication or bead beating, for example─is a key step in preparing extracts for cell-free expression systems. To create high protein-production capacity extracts, standard practice is to lyse cells sufficiently to thoroughly disrupt the membrane and thus extract expression machinery but without degrading that machinery. Here, we investigate the impact of different sonication energy inputs on the protein-production capacity of Escherichia coli extracts. While the existence of operator-specific optimal sonication energy inputs is widely known, our findings show that the sonication energy input that yields maximal protein output from a given expression template may depend on plasmid concentration, transcriptional and translational features (e.g., promoter), and other expression vector components (e.g., origin of replication). These results indicate that sonication protocols cannot be standardized to a single optimum, suggest strategies for improving protein yields, and more broadly highlight the need for better metrics and protocols for characterizing cell extracts.

FUS-mediated blood–brain barrier disruption for delivering anti-Aβ antibodies in 5XFAD Alzheimer’s disease mice

PurposeAmyloid-β (Aβ) peptides, the main component of amyloid plaques found in the Alzheimer's disease (AD) brain, are implicated in its pathogenesis, and are considered a key target in AD therapeutics. We herein propose a reliable strategy for non-invasively delivering a specific anti-Aβ antibody in a mouse model of AD by microbubbles-enhanced Focused Ultrasound (FUS)-mediated Blood–brain barrier disruption (BBBD), using a simple single stage MR-compatible positioning device.MethodsThe initial experimental work involved wild-type mice and was devoted to selecting the sonication protocol for efficient and safe BBBD. Pulsed FUS was applied using a single-element FUS transducer of 1 MHz (80 mm radius of curvature and 50 mm diameter). The success and extent of BBBD were assessed by Evans Blue extravasation and brain damage by hematoxylin and eosin staining. 5XFAD mice were divided into different subgroups; control (n = 1), FUS + MBs alone (n = 5), antibody alone (n = 5), and FUS + antibody combined (n = 10). The changes in antibody deposition among groups were determined by immunohistochemistry.ResultsIt was confirmed that the antibody could not normally enter the brain parenchyma. A single treatment with MBs-enhanced pulsed FUS using the optimized protocol (1 MHz, 0.5 MPa in-situ pressure, 10 ms bursts, 1% duty factor, 100 s duration) transiently disrupted the BBB allowing for non-invasive antibody delivery to amyloid plaques within the sonicated brain regions. This was consistently reproduced in ten mice.ConclusionThese preliminary findings should be confirmed by longer-term studies examining the antibody effects on plaque clearance and cognitive benefit to hold promise for developing disease-modifying anti-Aβ therapeutics for clinical use.

Pilot ex vivo study on non-thermal ablation of human prostate adenocarcinoma tissue using boiling histotripsy

Focused ultrasound technologies are of growing interest for noninvasive ablation of localized prostate cancer (PCa). Here we present the results of the first case study evaluating the feasibility of non-thermal mechanical ablation of human prostate adenocarcinoma tissue using the boiling histotripsy (BH) method on ex vivo tissue. High intensity focused ultrasound field was generated using a 1.5-MHz custom-made transducer with nominal F#=0.75. A sonication protocol of 734 W acoustic power, 10-ms long BH-pulses, 30 pulses per focal spot, 1 % duty cycle, and 1 mm distance between single foci was tested in an ex vivo human prostate tissue sample containing PCa. The protocol used here has been successfully applied in the previous BH studies for mechanical disintegration of ex vivo prostatic human tissue with benign hyperplasia. BH treatment was monitored using B-mode ultrasound. Post-treatment histologic analysis demonstrated BH produced liquefaction of the targeted tissue volume. BH treated benign prostate parenchyma and PCa had similar tissue fractionation into subcellular fragments. The results of the study demonstrated that PCa tumor tissue can be mechanically ablated using the BH method. Further studies will aim on optimizing protocol parameters to accelerate treatment while maintaining complete destruction of the targeted tissue volume into subcellular debris.

Treatment of mammary cancer with focused ultrasound: A pilot study in canine and feline patients

In recent years, veterinary medicine has expanded its practices beyond conventional methods, gradually integrating the Focused Ultrasound (FUS) technology in the care of companion animals like dogs and cats. The current study aimed to examine the feasibility and provide insights into the application of thermal FUS in canine and feline mammary cancer therapy. FUS was delivered by a 2-MHz single-element spherically focused ultrasonic transducer as integrated with an existing robotic positioning device. The functionality of the FUS system and sonication protocol in efficiently and safely ablating live tissue was initially validated in a rabbit thigh model in a laboratory environment. Nine (9) dogs and cats with superficial mammary cancer were recruited through a dedicated campaign according to specific safety criteria. The veterinary patients underwent FUS ablation followed by immediate surgical resection of the entire malignancy. Histopathology examination demonstrated well-defined regions of coagulative necrosis in all treated tumors with no off-target damage. Further study with a larger patient population is needed to confirm the current findings and demonstrate the safety and feasibility of complete FUS ablation of deep-seated tumors.

Greener and rapid synthesis of benzal-based Schiff base ligands as an efficient antibacterial, antioxidant, and anticancer agent

Using an ecologically friendly sonication protocol, certain benzal-based Schiff base ligands were produced by combining benzaldehyde and its para-derivatives with 2-(2-methoxyphenoxy)ethanamine. The reaction lasts around 2 min and yields 86.27% of the Schiff base ligands. Human tumor cell lines were used to test the ligand anticancer action and the results showed that MPEA-ANI (Antiproliferation of Breast cancer MDA MB 231 is 71% and Lung cancer A 549 is 85%) exhibits significant inhibition against both cell lines. Through the scavenging effects of ligands on DPPH, hydrogen peroxide, and nitric oxide radicals, the ligands antioxidant properties were investigated. The bacteria strains used to assess the antibacterial effectiveness of ligands were Bacillus subtilis, Staphylococcus aureus (Gram-positive bacteria), and Escherichia coli (Gram-negative bacterium). The ligands were described using elemental analysis, FT-IR, 1H NMR, 13C NMR, and mass spectroscopy.

Transcranial focused ultrasound and electrocorticography-based closed-loop epilepsy control system for an awake rat model

Abstract Neurostimulation with closed-loop interaction is one of the clinical solutions for patients with drug-resistant epilepsy. However, there are growing demands for an epilepsy control system with minimal invasiveness. Transcranial focused ultrasound (tFUS) is a promising non-invasive neuromodulation technique for controlling epileptic seizures due to its superior spatial specificity and depth penetrability. Here, we demonstrated a tFUS-based closed-loop system in combination with electrocorticography (ECoG), which provides precise monitoring of epileptic discharge for epileptic patients. In-house built 16-ch ECoG electrodes were attached to the Sprague-Dawley rat’s dura for detecting seizure spike-wave proceeding high-frequency oscillations (HFO) and monitoring epileptic discharges. After recovery from the surgery, kainic acid (5 mg/kg) was injected to generate a temporal lobe epilepsy rat model. An ultrasonic transducer operating at a fundamental frequency of 300 kHz was attached to the scalp for tFUS stimulation, which was automatically controlled by the system based on the HFO detection algorithm with real-time ECoG monitoring. The closed-loop tFUS stimulation on the right hippocampus with 40 Hz pulse-repetition frequency (PRF) and 5 % duty cycle induced the diminution of the duration of seizure spike-wave and the suppression of the power of brain oscillations such as theta, gamma bands from the bilateral hemisphere, compared to sham stimulation. Furthermore, the developed system is able to adjust the sonication protocol by monitoring seizure spike-wave. We therefore could provide optimized control of tFUS stimulation for seizure suppression. We demonstrated an ultrasound-based closed-loop system inhibiting epileptiform activity by providing tFUS stimulation before the generation of an epileptic spike-wave. The proposed system in this study shows the potential for developing a system that provides non-invasive seizure control without additional surgical burden for patients who are wearing medical brain implants such as ECoG or other types of intracranial EEG electrodes. Research Category and Technology and Methods Basic Research: 6. Pulsed Ultrasound (pUS) Keywords: transcranial focused ultrasound, closed-loop control, epilepsy, ECoG

Modelling transcranial ultrasound neuromodulation: an energy-based multiscale framework

Several animal and human studies have now established the potential of low intensity, low frequency transcranial ultrasound (TUS) for non-invasive neuromodulation. Paradoxically, the underlying mechanisms through which TUS neuromodulation operates are still unclear, and a consensus on the identification of optimal sonication parameters still remains elusive. One emerging hypothesis based on thermodynamical considerations attributes the acoustic-induced nerve activity alterations to the mechanical energy and/or entropy conversions occurring during TUS action. Here, we propose a multiscale modelling framework to examine the energy states of neuromodulation under TUS. First, macroscopic tissue-level acoustic simulations of the sonication of a whole monkey brain are conducted under different sonication protocols. For each one of them, mechanical loading conditions of the received waves in the anterior cingulate cortex region are recorded and exported into a microscopic cell-level 3D viscoelastic finite element model of a neuronal axon embedded in extracellular medium. Pulse-averaged elastically stored and viscously dissipated energy rate densities during axon deformation are finally computed under different sonication incident angles and are mapped against distinct combinations of sonication parameters of the TUS. The proposed multiscale framework allows for the analysis of vibrational patterns of the axons and its comparison against the spectrograms of stimulating ultrasound. The results are in agreement with literature data on neuromodulation, demonstrating the potential of this framework to identify optimised acoustic parameters in TUS neuromodulation. The proposed approach is finally discussed in the context of multiphysics energetic considerations, argued here to be a promising avenue towards a scalable framework for TUS in silico predictions. Statement of significanceLow-intensity transcranial ultrasound (TUS) is poised to become a leading neuromodulation technique for the treatment of neurological disorders. Paradoxically, how it operates at the cellular scale remains unknown, hampering progress in personalised treatment. To this end, models of the multiphysics of neurons able to upscale results to the organ scale are required. We propose here to achieve this by considering an axon submitted to an ultrasound wave extracted from a simulation at the organ scale. Doing so, information pertaining to both stored and dissipated axonal energies can be extracted for a given head/brain morphology. This two-scale multiphysics energetic approach is a promising scalable framework for in silico predictions in the context of personalised TUS treatment.

Neuromodulation Using Transcranial Focused Ultrasound on the Bilateral Medial Prefrontal Cortex.

Transcranial focused ultrasound (tFUS) is a promising technique of non-invasive brain stimulation for modulating neuronal activity with high spatial specificity. The medial prefrontal cortex (mPFC) has been proposed as a potential target for neuromodulation to prove emotional and sleep qualities. We aim to set up an appropriate clinical protocol for investigating the effects of tFUS stimulation of the bilateral mPFC for modulating the function of the brain-wide network using different sonication parameters. Seven participants received 20 min of 250 kHz tFUS to the bilateral mPFC with excitatory (70% duty cycle with sonication interval at 5 s) or suppressive (5% duty cycle with no interval) sonication protocols, which were compared to a sham condition. By placing the cigar-shaped sonication focus on the falx between both mPFCs, it was possible to simultaneously stimulate the bilateral mPFCs. Brain activity was analyzed using continuous electroencephalographic (EEG) recording during, before, and after tFUS. We investigated whether tFUS stimulation under the different conditions could lead to distinctive changes in brain activity in local brain regions where tFUS was directly delivered, and also in adjacent or remote brain areas that were not directly stimulated. This kind of study setting suggests that dynamic changes in brain cortical responses can occur within short periods of time, and that the distribution of these responses may differ depending on local brain states and functional brain architecture at the time of tFUS administration, or perhaps, at least temporarily, beyond the stimulation time. If so, tFUS could be useful for temporarily modifying regional brain activity, modulating functional connectivity, or reorganizing brain functions associated with various neuropsychiatric diseases, such as insomnia and depression.

The adsorbent for efficient iodine capture based on citrazinic acid and cytosine: experimental synthesis with a simple way and property analysis with electronic structure calculations

Radioactive iodine, one type of nuclear waste, is harmful to the environment and human health due to its long half-life and volatility. Therefore, designing and synthesizing low-cost and easily-made materials for the effective adsorption of radioiodine is widely concerned. Herein, a biscuit-shaped new material was synthesized by a grinding-mixing coupled with sonication protocol through self-assembly interactions between citrazinic acid (CA) and cytosine (CY) aiming to achieve the iodine capture from both vapor and solution. Electronic structure calculations were used to reveal the adsorption mechanism. The results showed that the high uptake of iodine by CACY originates from the charge transfer via CACY to the antibonding molecular orbital (σ∗) of I2. Meanwhile, trouble-free entry pore sizes of CACY also contribute to the physisorption of molecular iodine. Besides, the iodine molecule is preferentially perpendicularly adsorbed on the carbon atom of the CA ring. Moreover, CACY exhibits a high capture for iodine in hexane following pseudo-second-order kinetics and fitting the Langmuir isotherm model. This work presents a facile and inexpensive synthesis approach for radioiodine adsorption materials and provides new insights into the interaction mechanism between the self-assembled materials and the adsorbates.

Optoacoustic/Fluorescent/Acoustic Imaging Probe Based on Air-Filled Bubbles Functionalized with Gold Nanorods and Fluorescein Isothiocyanate.

Liquid/surfactant/gas interfaces are promising objects for nanoengineered multimodal contrasts, which can be used for biomedical imaging in preclinical and clinical applications. Microbubbles with the gaseous core and shell made of lipids/proteins have already acted as ultrasound (US) contrast agents for angiography. In the present work, microbubbles with a shell composed of Span 60 and Tween 80 surfactants functionalized with fluorescein isothiocyanate and gold nanorods to achieve a multimodal combination of US, fluorescence, and optoacoustic imaging are described. Optimal conditions for microbubble generation by studying the surface tension of the initial solutions and analyzing the size, stability, and charge of the resulting bubbles were found. By controlling and modifying bubbles’ surface properties, an increase in stability and storage time can be achieved. The functionalization of bubbles with gold nanoparticles and a dye by using an optimally selected sonication protocol was performed. The biomedical application’s potential in imaging modalities of functionalized microbubbles using a medical US device with a frequency of 50 MHz, fluorescence tomography, and raster-scanning optoacoustic mesoscopy measurements was evaluated. The obtained results are important for optimum stabilization and functionalization of gas/liquid interfaces and the following applications in the multimodal biomedical imaging.

Method of extraction and proteome profiling of mycobacteria using liquid chromatography-high resolution mass spectrometry

Advances in massively parallel sequencing, of complete bacterial genomes, have led to many novel findings in the field of genomics. However, these data often lack correlation with expressed protein profiles. It has been demonstrated that even very closely related genomes, such as in mycobacteria, express drastically different phenotypes. These phenotypes often have major roles in pathogenicity. Therefore, it is just as important to have a method for examining the proteome of a bacterium as well as its genome. These studies are further complicated in mycobacteria due to the cell wall and mycolic acid. A comprehensive method for the identification and characterization of the whole mycobacterium protein profile is needed. In the present study, a simple, sensitive, and specific liquid chromatography tandem mass spectrometry method was developed for the extraction, purification and profiling the mycobacterial proteome in various species. During development, sonication and bead-beating cell lysis protocol was tested using 15% Acetonitrile and 6 M guanidine-HCl (GuHCl) as extraction solvent. Sonication lysis in 6 M GuHCl with glass beads was the preferred method for cell lysis. This method was developed using reverse phase liquid chromatography and a Q Exactive ™ Plus Orbitrap™ mass spectrometer for peptide and protein identification. Bottom-up liquid chromatography-mass spectrometry LC–MS analysis resulted in identification of greater than 2500 proteins.

Magnetic Resonance Methods for Focused Ultrasound-Induced Blood-Brain Barrier Opening

Since its discovery in 2001, the interest in the low-intensity focused ultrasound (FUS)-mediated blood-brain barrier (BBB) disruption to deliver genes and drugs to brain tissue has increased steadily. Increasingly sophisticated sonication protocols and dedicated hardware are being developed to efficiently and safely permeabilize the BBB, and novel magnetic resonance (MR)-based technologies have been designed to guide FUS-induced BBB opening protocols. MR imaging (MRI) allows not only to more precisely target brain regions and evaluate the outcome of sonication in terms of enhanced BBB permeability but also to control the effects of ultrasound on brain structure and function. This review summarizes the state of the art in current MRI hardware and methods used in BBB opening protocols both in pre-clinical and clinical settings.

Improvement of Mycobacterium tuberculosis detection in sputum using DNA extracted by sonication

Tuberculosis (TB) is one of the infectious diseases with high mortality in the world. DNA amplification techniques have been used to overcome barriers to the diagnosis of this disease. However, the success of these methodologies is highly dependent on the DNA obtained from the sample. This study was carried out to verify whether the DNA extracted by sonication (in house method) could yield suitable DNA for amplification by real-time PCR (qPCR). Sixty sputum samples were submitted to DNA extraction using sonication compared to a commercial method (Detect-TB kit, Labtest/MG-Brazil). All DNA samples were amplified by qPCR for IS6110 region (IS6110-qPCR/SYBR Green assay). Out of 60 samples, 40 were positive for TB; of these, all had positive results when extracted by sonication (100%) and 80% when extracted by the commercial method. The limit of detection (LOD) of Mycobacterium tuberculosis (H37Rv strain) by qPCR was 14 CFU/mL when the DNA was extracted by sonication, compared to countless colonies when extracted by commercial kit. In conclusion, the sonication protocol (without purification step) proved to be a simple, fast, and suitable method for obtaining DNA for use in qPCR from sputum samples.

Usefulness of sonication procedure in mesh infection diagnosis associated with hernia repair.

The use of prosthetic meshes is a common practice in hernia repair surgery. However, infection can appear as an important complication where antibiotic selection must be directed by the etiology of the infection. In recent years, sonication has appeared as an important tool for the diagnosis of many biomaterial-associated infections. Here, we evaluated our experience with this methodology for the diagnosis of mesh infection. We retrospectively reviewed the microbiological records between 2015 and 2019 looking for sonicated meshes in the microbiology laboratory. All samples were processed according to the sonication protocol described by Esteban J et al. (J Clin Microbiol. 2008 Feb; 46 (2): 488-92). 26 samples were processed during the study period. 21 of them gave a positive result for culture (11 polymicrobial and 10 monomicrobial ones). Staphylococcus aureus and Candida albicans were the commonest monomicrobial isolates (4 cases each). There were five cases of mixed gut microbiota. The median (interquartile range) UFC count was > 100,000 (50,000- > 100,000) CFU/mL. Sonication is a useful technique for the diagnosis of mesh infection.

Sonication Leads to Clinically Relevant Changes in Treatment of Periprosthetic Hip or Knee Joint Infection.

Background: Diagnosis of periprosthetic joint infection (PJI) can be troublesome. Sonication can be a helpful tool in culturing bacteria that are difficult to detect with standard tissue cultures. Aim of this study is to evaluate the clinical importance of our standardized sonication protocol in detecting periprosthetic joint infection.Materials and methods: All patients with revision surgery of a hip or knee prosthesis between 2011 and 2016 were retrospectively reviewed and divided in two groups: clinically suspected of infection or not suspected of infection. For both tissue culture and implant sonication, calculations of sensitivity and specificity were performed. Clinical relevance of sonication was evaluated by calculating in which percentage of patients' sonication influenced clinical treatment.Results: 226 patients with revision of a total hip prosthesis (122 patients) or a total knee prosthesis (104 patients) were included. Sensitivity of perioperatively taken tissue cultures was 94.3% and specificity was 99.3%. For sonication sensitivity was 80.5% and specificity was 97.8%.In the infection group eight patients (9%) with only one positive tissue culture and a positive sonication fluid culture with the same pathogen were found.Interpretation: Although sensitivity and specificity of sonication was lower compared to tissue cultures, periprosthetic joint infection could only be established in 8 patients (9%) suspected of infection because of a positive result of the sonication fluid culture.Sonication leads to clinically relevant changes in treatment and seems therefore to be a helpful diagnostic tool in clinical practice.