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We report a patient with tremor-dominant Parkinson's disease who had a mild cavitation bioeffect during magnetic resonance-guided focused ultrasound thalamotomy. During the aligning phase with low-energy sonication, cavitation caused mild dysarthria and paresthesia, prompting treatment cessation. At the same time, tremor and rigidity improved. MRI revealed extensive high-intensity lesions in the thalamus 1 day after the procedure followed by steroid infusion, which resulted in resolution of adverse events. Tremor and rigidity improved 1.5 years after the procedure. Although cavitation can relieve tremors and rigidity, it should be carefully monitored due to potential permanent adverse events by unpredictable and unknown behaviors.

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RATIONALE: Assessment of the bioeffect of serotonin reuptake inhibitors (SRIs, including both selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs)) at the serotonin transporter (SERT) in patients and healthy controls can have important theoretical and clinical implications. OBJECTIVES: Bioeffect at SERT has been assessed by neuroimaging of brain SERT occupancy, through in vitro measurements of platelet serotonin (5-HT) uptake, and by measuring platelet 5-HT content pre- and post-initiation of SRI administration. Studies of platelet 5-HT content were reviewed in order to (1) determine the overall apparent bioeffect of SRIs; (2) compare bioeffect across types of SRIs; (3) compare the three approaches to assessing SRI bioeffect; and (4) determine how the findings might inform clinical practice. METHODS: We performed a systematic review of the published studies that measured platelet 5-HT content to assess SRI bioeffect at the platelet SERT. Studies using neuroimaging and in vitro platelet 5-HT uptake to assess SRI bioeffect were reviewed for comparison purposes. RESULTS: Clinical doses of SRIs typically resulted in 70-90% reductions in platelet 5-HT content. The observed bioeffect at the platelet SERT appeared similar among different SSRIs and SNRIs. The bioeffect estimations based on platelet 5-HT content were consistent with those obtained using neuroimaging to assess brain SERT occupancy and those based on the in vitro measurement of platelet 5-HT uptake. CONCLUSIONS: In general, excellent agreement was seen in the apparent SRI bioeffect (70-90% inhibition) among the platelet 5-HT content studies and across the three bioeffect approaches. Theoretical and practical clinical implications are discussed.

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As a kind of novel functional material, graphene-related nanomaterials (GRMs) have great potentials in industrial and biomedical applications. Meanwhile, the production and wide application of GRMs will increase the risk of unintended or intentional oral exposure to human beings, attracting safety concerns about their biological fates and toxicological effects. The normal enzymatic activity of digestive enzymes is essential for the proper functioning of the gastrointestinal tract system. However, whether and how orally entered GRMs and their surface groups affect digestive enzymes' activity are still scarce. In this paper, we systematically studied the effects of graphene oxide (GO), graphene modified with hydroxyl groups (OH-G), carboxyl groups (COOH-G), and amino groups (NH2-G) on enzymatic activity of three typical digestive enzymes (pepsin, trypsin, and α-pancreatic amylase). The results showed that the activity of trypsin and α-pancreatic amylase could be greatly changed after GRMs incubation in a surface chemistry dependent manner, while the activity of pepsin was not affected. To elucidate the mechanisms at the molecular level, the interactions between trypsin and GRMs were studied by spectrometry, thermophoresis, and computational simulation approaches, and the key roles of surface chemistry of GRMs in tailoring the activity of trypsin were finally figured out. GO allosterically inhibited trypsin's activity in the non-competitive manner because of the conformation transition induced by the intensive interactions. COOH-G could effectively hamper enzymatic activity of trypsin in the competitive manner by blocking the active catalytic pocket. As for NH2-G and OH-G, they had little impact on the activity of trypsin due to the weak binding affinity or limited conformational change. Our findings not only indicate surface chemistry plays an important role in tailoring the effects of GRMs on the activity of digestive enzymes but also provide new insights for understanding the oral safety of nanomaterials from daily products and the environment.

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Improving anti-tumor immunity has promising outcomes in eradicating malignant tumors. Tumor cells can escape from immune surveillance and killing; therefore, various strategies are continuously developing to inhibit immune escape. Focused ultrasound (FUS) has recently emerged to play an important role in immune modulation. After FUS therapy, various tumor antigens and related signals are released. The non-thermal effect of FUS strengthens the blood and lymph circulation, increases cell permeability, and helps in crossing the physical barrier like the blood-brain barrier and blood-tumor barrier. However, the different ablation of FUS is proposed to have a different anti-tumor immune effect. Therefore, we categorized the FUS ablation into thermal and non-thermal ablation and summarized possible anti-tumor immunity mechanisms.

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Purpose: This study compares photon and proton therapy plans for patients with synchronous bilateral early breast cancer and estimates risks of early and late radiation-induced toxicities. Materials and Methods: Twenty-four patients with synchronous bilateral early breast cancer receiving adjuvant radiation therapy using photons, 3-dimensional conformal radiation therapy or volumetric modulated arc therapy, were included and competing pencil beam scanning proton therapy plans were created. Risks of dermatitis, pneumonitis, acute esophageal toxicity, lung and breast fibrosis, hypothyroidism, secondary lung and esophageal cancer and coronary artery events were estimated using published dose-response relationships and normal tissue complication probability (NTCP) models. Results: The primary clinical target volume V95% and/or nodal clinical target volume V90% were less than 95% in 17 photon therapy plans and none of the proton plans. Median NTCP of radiation dermatitis ≥ grade 2 was 18.3% (range, 5.4-41.7) with photon therapy and 58.4% (range, 31.4-69.7) with proton therapy. Median excess absolute risk (EAR) of secondary lung cancer at age 80 for current and former smokers was 4.8% (range, 0.0-17.0) using photons and 2.7% (range, 0.0-13.6) using protons. Median EAR of coronary event at age 80, assuming all patients have preexisting cardiac risk factors, was 1.0% (range, 0.0-5.6) with photons and 0.2% (range, 0.0-1.3) with protons. Conclusion: Proton therapy plans improved target coverage and reduced risk of coronary artery event and secondary lung cancer while increasing the risk of radiation dermatitis.

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Lotus (Nelumbo nucifera) was used as model plant in this study to explore its physiology and molecular response upon short-term exposure to silver nano-particles (AgNPs). Accumulation patterns demonstrated a potential uptake of AgNPs by roots and transport to the leaves as a likely key translocation route in lotus. AgNPs exposure was negatively correlated with lotus growth, including germination rate and petiole length in a concentration-dependent manner. Synthesis of chloroplast pigments in lotus leaves was enhanced by low AgNPs concentration, but were inhibited at high concentration. Hydrogen peroxide (H2O2) was detected in lotus leaves after AgNPs treatment. Proline accumulation in lotus leaves was induced with the increase in AgNPs concentration and exposure time. Antioxidant enzyme activities of superoxide dismutase (SOD), peroxidase (POD) as well as catalase (CAT) were enhanced after the first day of AgNPs exposure, but declined with increased exposure time, indicating a time-dependent toxicity of AgNPs. In addition, real-time PCR revealed that two detoxification-related genes, GSH1 and GST, could be activated on the first day of AgNPs exposure, but down-regulated with prolonged AgNPs treatment. Photosynthesis-related RbcS gene was up-regulated, however, no obvious difference in the expression of RbcL was observed after the first day of AgNPs exposure. Moreover, WRKY70a and WRKY70b transcription factors exhibited similar expression patterns, with the highest induction after a 5 mg/L AgNPs exposure on the first day, which decreased with prolonged exposure time. This study provides useful references for further evaluation of the toxic mechanism of AgNPs and their bio-effects on aquatic plants and ecosystems.

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Fluorinated graphene (F-GRA) has attracted great interest in biomedical applications. In this context, the direct interaction between F-GRA and various biomolecules is a vital process guiding the bio-function of this nanomaterial. Nevertheless, information regarding the interaction of F-GRA with biomolecules is scarce, particularly at the molecular level. In this study, using an in silico approach, we investigate the adsorption of F-GRA to a phospholipid bilayer to evaluate the potential effect of the nanomaterial to a biomembrane and its mechanism. Our results indicate that F-GRA can either slightly insert into the membrane or parallelly adhere on the membrane surface, different from the complete insertion of graphene. Detailed analysis confirms that the electrostatic forces dominantly mediate the adsorption process. F-GRA in its parallel binding pattern causes a partial enlargement in the membrane thickness via the disruption of the lipids' order parameters, indicating a mild mechanical influence to the membrane structure. Although the potential mechanical perturbation of F-GRA to membrane is detected, this impact is much weaker than graphene. These findings suggest the potentially weak physical perturbations of F-GRA to the cellular membrane, which may establish the basis for the future biomedical applications of this material after proper surface coating.

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We recently proposed an analytical design method of Langevin transducers for therapeutic ultrasound treatment by conducting parametric study to estimate the effect of compression force on resonance characteristics. In this study, experimental investigations were further performed under various electrical conditions to observe the acoustic power of the fully equipped transducer and to assess its heat-related bioeffect. Thermal index (TI) tests were carried out to examine temperature rise and thermal damage induced by the acoustic energy in fatty porcine tissue. Acoustic power emission, TI values, temperature characteristics, and depth/size of thermal ablation were measured as a function of transducer's driving voltage. By exciting the transducer with 300 Vpp sinusoidal continuous waveform, for instance, the average power was 23.1 W and its corresponding TI was 4.1, less than the 6 specified by the Food and Drug Administration (FDA) guideline. The maximum temperature and the depth of the affected site were 74.5 °C and 19 mm, respectively. It is shown that thermal ablation is likely to be more affected by steep heat surge for a short duration rather than by slow temperature rise over time. Hence, the results demonstrate the capability of our ultrasonic transducer intended for therapeutic procedures by safely interrogating soft tissue and yet delivering enough energy to thermally stimulate the tissue in depth.

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Recently, the novel hole-containing carbon nitride C3N3 nanomaterial was successfully synthesized, featuring outstanding and unique mechanical and electrical properties. However, to fully exploit this nanomaterial in biomedical applications, information regarding its biocompatibility is necessary. Herein, by using all-atom molecular dynamics simulations, we evaluate the interactions between a C3N3 nanosheet and a critical cellular component, that is, a lipid membrane bilayer. Our results indicate that the C3N3 nanosheet is able to interact with the lipid bilayer surface without affecting the membrane's structural integrity. Moreover, our results showed that the C3N3 nanosheet is adsorbed on the surface of the lipid bilayer without inflicting any structural damage to the membrane, regardless of the conditions of the system (that is, with and without restrains in the C3N3 nanosheet). Also, we found that both energy contributions, namely vdW and Coulomb energies, conjointly mediated the C3N3 adsorption process. In comparison and as expected, pristine graphene significantly disturbed the membrane structure. Perpendicularly-oriented-sheet simulations described the significance of the surface charges of the C3N3 nanosheet in prohibiting its insertion into the membrane. Detailed analysis indicated that the electrostatic attraction between the pores in the C3N3 structure and the lipid head amino groups stabilized the interaction restricting the insertion of the C3N3 structure deeper into the membrane. Our results suggested the importance of the negatively charged C3N3 pores when interacting with lipid membranes. Our findings shed light on the potential compatibility of C3N3 with biomembranes and its underlying molecular mechanism, which might provide a useful foundation for the future exploration of this 2D nanomaterial in biomedical applications.

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This study based on the freshwater algae Spiny scenedesmus (S. scenedesmus) with tolerance to venlafaxine aiming to investigate algae removal abilities. Here presented for the first time to evaluate the effect of ß-cyclodextrin (ß-CD) on reduce toxicity and enhance removal ability of venlafaxine and O-desmethylvenlafaxine to S. scenedesmus. Based on dose-response results, the toxicity of R-venlafaxine (EC50 = 6.81 mg·L -1) and R-O-desmethylvenlafaxine (EC50 = 3.36 mg·L -1) to algae were more than two times than those in the presence of ß-CD treatment (10.64 mg L -1 for R-venlafaxine and 11.87 mg L -1 for R-O-desmethylvenlafaxine). The significant differences were observed between S-venlafaxine (11.07 mg L -1) and S-O-desmethylvenlafaxine (10.24 mg L -1), which were more toxic than R-forms. The half-lives of R- and S-venlafaxine were 0.8 d and 0.5 d in the presence of ß-CD, which were obvious shorter than those in alone treatments. In addition, our experiments not only demonstrated that ß-CD performed particularly well for removal of venlafaxine and O-desmethylvenlafaxine, it significantly reduces the toxicity of venlafaxine to alga. These results highlight advantages of ß-CD relevant to chiral drugs removal and protection of aquatic organisms, which may have a better application for environmental and ecological safety in future.

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Many useful therapeutic bio-effects can be generated using ultrasound-induced cavitation. However, cavitation is also capable of causing unwanted cellular and vascular damage, which should be monitored to ensure treatment safety. In this work, the unique opportunity provided by passive acoustic mapping (PAM) to quantify cavitation dose across an entire volume of interest during therapy is utilised to provide setup-independent measures of spatially localised cavitation dose. This spatiotemporally quantifiable cavitation dose is then related to the level of cellular damage generated. The cavitation-mediated destruction of equine red blood cells mixed with one of two types of cavitation nuclei at a variety of concentrations is investigated. The blood is placed within a 0.5-MHz ultrasound field and exposed to a range of peak rarefactional pressures up to 2 MPa, with 50 to 50,000 cycle pulses maintaining a 5% duty cycle. Two co-planar linear arrays at 90° to each other are used to generate 400-µm-resolution frequency domain robust capon beamforming PAM maps, which are then used to generate estimates of cavitation dose. A relationship between this cavitation dose and the levels of haemolysis generated was found which was comparable regardless of the applied acoustic pressure, pulse length, cavitation agent type or concentration used. PAM was then used to monitor cellular damage in multiple locations within a tissue phantom simultaneously, with the damage-cavitation dose relationship being similar for the two experimental models tested. These results lay the groundwork for this method to be applied to other measures of safety, allowing for improved ultrasound monitoring of cavitation-based therapies.

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BACKGROUND: Biological safety of ultrasound is a complex and nuanced subject that is poorly understood by ultrasound users. Little is known about the acoustic output and thermal index levels during the routine use of modern ultrasound machines in prenatal scanning. METHODOLOGY: This study was a retrospective review of thermal index (TI) values encountered during 300 prenatal ultrasound examinations (100 in each trimester) performed on any one of 13 Philips Epiq 7 or Epiq 5 systems, representing approximately 106.5 h of real-time scanning. The TI levels were compared to three international guidelines on the biological safety of ultrasound. RESULTS: The routine use of current Philips systems was associated with low TI levels. Of the 300 examinations reviewed, virtually all were compliant with the BMUS and Nelson safety guideline. Whether the examination was compliant with the WFUMB guideline is open to interpretation. The highest level of TI encountered was 1.1. In no instance did the TI level incur into the 'not recommended' range or into a range where specific user action was required to reduce the TI within 1 min. The most frequent action associated with TI > 0.7 was the use of M-mode to document the fetal heart rate. In the four instances where TI peaked at 1.1, 3 were associated with the use of M-mode and one with B-mode. Spectral Doppler was not implicated in high TI levels. These results are surprising and open up a range of opportunities for future study.

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Controversial, sensational and often contradictory scientific reports have triggered active debates over the biological effects of electromagnetic fields (EMFs) in literature and mass media the last few decades. This could lead to confusion and distraction, subsequently hampering the development of a univocal conclusion on the real hazards caused by EMFs on humans. For example, there are lots of publications indicating that EMF can induce apoptosis and DNA strand-breaks in cells. On the other hand, these effects could rather be beneficial, in that they could be effectively harnessed for treatment of various disorders, including cancer. This review discusses and analyzes the results of various in vitro, in vivo and epidemiological studies on the effects of non-ionizing EMFs on cells and organs, including the consequences of exposure to the low and high frequencies EM spectrum. Emphasis is laid on the analysis of recent data on the role of EMF in the induction of oxidative stress and DNA damage. Additionally, the impact of EMF on the reproductive system has been discussed, as well as the relationship between EM radiation and blood cancer. Apart from adverse effects, the therapeutic potential of EMFs for clinical use in different pathologies is also highlighted.

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BACKGROUND: We aimed to investigate the influence of nursing intervention on recurrent vulvovaginal candidiasis (RVVC) patients treated with adenosine triphosphate (ATP)-infrared bio-effect technique. METHODS: Sixty eight RVVC patients of Women & Children's Health Care Hospital of Linyi were randomly divided into intervention group (n=34) and control group (n=34) from to June, 2016 to June 2017. Patients in intervention group received the one-to-one intervention based on ATP-infrared bio-effect technique; the individualized nursing intervention program was developed. Patients in control group were treated with routine nursing for vaginitis and follow-up. The intervention effect was evaluated via clinical efficacy and MOS 36-item short-form health survey (SF-36) scale. RESULTS: After the total course of treatment, there was significant difference in the cure rate between the two groups of patients (P<0.05). 1 month after all courses of treatment, the scores of physical functioning (PF), mental health (MH), vitality (V) and bodily pain (BP) in intervention group were higher than those in control group, displaying statistically significant differences (P=0.029; P=0.049; P=0.042; P=0.039, respectively). 6 months after the total course of treatment, the score of each dimension in intervention group was higher than that in control group during the same period (P<0.01). CONCLUSION: Nursing intervention can increase the cure rate, change the adverse cognition and improve the quality of life of RVVC patients treated with ATP-infrared bio-effect technique.

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Low-boiling-point perfluorocarbon phase-change contrast agents (PCCAs) provide an alternative to microbubble contrast agents. Although parameter ranges related to in vivo bio-effects of microbubbles are fairly well characterized, few studies have been done to evaluate the potential of bio-effects related to PCCAs. To bridge this gap, we present an assessment of biological effects (e.g., hemorrhage) related to acoustically excited PCCAs in the rodent kidney. The presence or absence of bio-effects was observed after sonication with various perfluorocarbon core PCCAs (decafluorobutane, octafluoropropane or a 1:1 mixture) and as a function of activation pulse mechanical index (MI; minimum activation threshold, which was a moderate MI of 0.81-1.35 vs. a clinical maximum of 1.9). Bio-effects on renal tissue were assessed through hematology and histology including measurement of blood creatinine levels and the quantity of red blood cell (RBC) casts present in hematoxylin and eosin-stained kidney tissue sections after sonication. Short-term (24 h) and long-term (2 and 4 wk) analyses were performed after treatment. Results indicated that bio-effects from PCCA vaporization were not observed at lower mechanical indices. At higher mechanical indices, bio-effects were observed at 24 h, although these were not observable 2 wk after treatment.

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Carbon nanoparticles (CNPs) have been widely used in tumor drainage lymph node (TDLN) imaging, drug delivery, photothermal therapy, and so on. However, during the theranostic applications, the accumulation efficiency of CNPs in target organs is unknown yet, which largely hinders the extension of CNPs into clinical uses. Herein, we prepared skeleton-labeled 13C-CNPs that had identical properties to commercial CNPs suspension injection (CNSI) for the imaging and quantification in TDLN. 13C-CNPs were prepared by arc discharge method, followed by homogenization with polyvinylpyrrolidone. The size distribution and morphology of 13C-CNPs were nearly the same as those of CNSI under transmission electron microscope. The hydrodynamic radii of both 13C-CNPs and CNSI were similar, too. According to X-ray photoelectron spectroscopy and infrared spectroscopy analyses, the chemical compositions and chemical states of elements were also nearly identical for both labeled and commercial forms. The skeleton labeling of 13C was reflected by the shift of G-band toward lower frequency in Raman spectra. 13C-CNPs showed competitive performance in TDLN imaging, where the three lymph nodes (popliteal lymph node, common iliac artery lymph node, and paraaortic lymph node) were stained black upon the injection into the hind extremity of mice. The direct quantification of 13C-CNPs indicated that 877 µg/g of 13C-CNPs accumulated in the first station of TDLN (popliteal lymph node). The second station of TDLN (common iliac artery lymph node) had even higher accumulation level (1,062 µg/g), suggesting that 13C-CNPs migrated efficiently along lymphatic vessel. The value decreased to 405 µg/g in the third station of TDLN (paraaortic lymph node). Therefore, the 13C-CNPs provided quantitative approach to image and quantify CNSI in biological systems. The implication in biomedical applications and biosafety evaluations of CNSI is discussed.

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The dramatically different bio-effects of graphene and graphene oxide (GO) have been widely observed in diverse biological systems, which determine the applications and toxicity of graphene materials. To elucidate the mechanism at molecular level, it is urgent to investigate the enzyme-graphene interaction and its consequences. In this study, we comparatively studied the influence of GO and reduced GO (RGO) on the activity and conformation of lysozyme to provide better understandings of their different bio-effects. Both GO and RGO adsorbed large quantities of lysozyme after incubation. GO inhibited lysozyme activity seriously, while RGO nearly had no influence on the enzyme activity. The different inhibitions of enzyme activity could be explained by the lysozyme conformational changes, where GO induced more changes to the protein conformation according to UV-vis absorbance, far-UV circular dichroism spectra, intrinsic fluorescence quenching, and infrared spectra. Based on the spectroscopic changes of lysozyme, GO induced the loss of secondary structure and exposed the active site of lysozyme more to the aqueous environment. In addition, neither GO nor RGO induced the fibrillation of lysozyme after 12d incubation. The results collectively indicated that the oxidation degree significantly impacted the enzyme-graphene interaction. The implications to the designs of enzyme-graphene system for bio-related applications and the toxicological effects of graphene materials are discussed.

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Objective To explore the bioeffect of different parameters on 4 cell lines by ultrasoundmediated microbubble destruction.Methods The orthogonal experimental design was used to investigate the effect of three factors on the bioeffects of four cell lines under three levels.Three factors included microbubble concentration,sound intensity,irradiation time.Human breast tumor (MCF-7) cells,ovarian tumor (A2780) cells,liver tumor (Bel7402) cells and thyroid tumor (ARO) cells were exposed to ultrasound in the presence of SonoVue.The cell survival rate was determined by MTT methods and the cell luminosity factor was detected by flow cytometry.Results The optimum parameters for Bel7402 and ARO cell were the same (A2B3C2),and they were different from those from MCF-7 (A3B1C1) and A2780 (A1B3C3) cell.The cell survival rates for 4 cell lines were above 75％,and the cell luminosity factors were different among 4 cell lines.Conclusions The optimum parameters by ultrasound-mediated microbubble destruction for different cell lines are different,and under the optimum parameters the bioeffects of different cell lines are different.

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BACKGROUND: Occupational exposure to trichloroethylene (TCE) has been linked to adverse health outcomes including non-Hodgkin's lymphoma and kidney and liver cancer; however, TCE's mode of action for development of these diseases in humans is not well understood. METHODS: Non-targeted metabolomics analysis of plasma obtained from 80 TCE-exposed workers [full shift exposure range of 0.4 to 230 parts-per-million of air (ppma)] and 95 matched controls were completed by ultra-high resolution mass spectrometry. Biological response to TCE exposure was determined using a metabolome-wide association study (MWAS) framework, with metabolic changes and plasma TCE metabolites evaluated by dose-response and pathway enrichment. Biological perturbations were then linked to immunological, renal and exposure molecular markers measured in the same population. RESULTS: Metabolic features associated with TCE exposure included known TCE metabolites, unidentifiable chlorinated compounds and endogenous metabolites. Exposure resulted in a systemic response in endogenous metabolism, including disruption in purine catabolism and decreases in sulphur amino acid and bile acid biosynthesis pathways. Metabolite associations with TCE exposure included uric acid (ß = 0.13, P-value = 3.6 × 10-5), glutamine (ß = 0.08, P-value = 0.0013), cystine (ß = 0.75, P-value = 0.0022), methylthioadenosine (ß = -1.6, P-value = 0.0043), taurine (ß = -2.4, P-value = 0.0011) and chenodeoxycholic acid (ß = -1.3, P-value = 0.0039), which are consistent with known toxic effects of TCE, including immunosuppression, hepatotoxicity and nephrotoxicity. Correlation with additional exposure markers and physiological endpoints supported known disease associations. CONCLUSIONS: High-resolution metabolomics correlates measured occupational exposure to internal dose and metabolic response, providing insight into molecular mechanisms of exposure-related disease aetiology.

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Mass stranding of cetaceans (whales and dolphins), in close association with the activity of naval sonar systems, has been reported on numerous occasions. Necropsy showed bubble-associated lesions similar to those described in human decompression sickness (DCS). We examined the hypothesis that exposure to underwater sound may potentiate DCS. Rats were subjected to immersion and simulated dives with and without simultaneous acoustic transmissions at pressure levels and frequencies of 204 dB/8 kHz and 183.3 dB/15 kHz. DCS severity was assessed using the rotating wheel method. Recording of somatosensory evoked potentials (SSEPs) was employed under general anesthesia as an electrophysiological measure of neurologic insult. A significantly higher rate of decompression sickness was found among animals exposed to the 204-dB/8-kHz sound field. Significantly higher pathological SSEPs scores were noted for both underwater sound protocols. Pathological SSEPs scores in animals immersed during the acoustic transmissions, but without changes in ambient pressure, were comparable to those observed in animals exposed to the dive profile. The results demonstrate induction of neurological damage by intense underwater sound during immersion, with a further deleterious effect when this was combined with decompression stress. The study outcome has potential implications for human diving safety and may provide an explanation for the mass stranding of cetaceans purportedly associated with sonar activity.

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