[Research Progress on Forensic Toxicology of Z-drugs].

The Z-drugs (zolpidem, zopiclone, and zaleplon), as the innovative hypnotics, have an improvement over the traditional benzodiazepines in the management of insomnia. Z-drugs have significant hypnotic effects by reducing sleep latency and improving sleep quality, though duration of sleep may not be significantly increased. As benzodiazepines, Z-drugs exert their effects through increasing the transmission of γ-aminobutyric acid. Z-drugs overdose are less likely to be fatal, more likely would result in poisoning. Z-drugs can be detected in blood, urine, saliva, and other postmortem specimens through liquid chromatography-mass spectrometry techniques. Zolpidem and zaleplon exhibit significant postmortem redistribution. Z-drugs have improved pharmacokinetic profiles, but incidence of neuropsychiatric sequelae, poisoning, and death may prove to be similar to the other hypnotics. This review focuses on the pharmacology and toxicology of Z-drugs with respect to their adverse effect profile and toxicity and toxicology data in the field of forensic medicine.

[Theoretical analysis of the residual amplitude modulation of frequency modulation strong absorption spectroscopy].

The application of frequency modulation (FM) spectroscopy technology in the trace gas detection is greatly restricted by the residual amplitude modulation (RAM) which induced by the birefringence of the electro-optic modulator (EOM) and the misaligned linear polarization direction of laser to the EOM. Based on the interaction between the laser field and crystal, a line-shape expression of the FM spectroscopy with RAM is obtained. The angle between the polarization direction of input light and the principle axis of EOM, theta, the phase difference between the two principle axes of electro-optic crystal, delta phi, and the modulation index FM, beta, are the major factors to influence the lineshape. The larger theta and larger delta phi are, the stronger distortion of the lineshape is. Meanwhile a DC offset exists in the FM dispersion spectroscopy which is influenced by theta and delta phi. Finally a servo control of theta and delta phi is suggested to reduce the RAM. These phenomenon and the analysis of the lineshape provide a necessary technical support for the fiber components based FM spectroscopy.

[Research on the carbon content of coal by LIBS].

A method is introduced about quantitative analysis of carbon in coal by LIBS (laser-induced breakdown spectroscopy) in the present paper, and it introduces data optimization technology and method based on spectral data integration, normalization and data screening processing to overcome the poor quality of precision in the analysis because of laser source energy fluctuation, self-absorption, sample surface roughness etc. It is showed that the standard deviation (SD) is less than 1.6% using the method to analyze C element content in coal, and this method also can be used for other element analysis for coal.

[Analysis of software for identifying spectral line of laser-induced breakdown spectroscopy based on LabVIEW].

Self-designed identifying software for LIBS spectral line was introduced. Being integrated with LabVIEW, the soft ware can smooth spectral lines and pick peaks. The second difference and threshold methods were employed. Characteristic spectrum of several elements matches the NIST database, and realizes automatic spectral line identification and qualitative analysis of the basic composition of sample. This software can analyze spectrum handily and rapidly. It will be a useful tool for LIBS.

Dose-response relationship of blood flow restriction training on isometric muscle strength, maximum strength and lower limb extensor strength: A meta-analysis.

Objective: To perform a meta-analysis on the efficacy and dose-response relationship of blood flow restriction training on muscle strength reported worldwide. Methods: Thirty-four eligible articles with a total sample size of 549 participants were included in the meta-analysis. This study was performed using the method recommended by the Cochrane Handbook (https://training.cochrane.org/handbook), and the effect size was estimated using the standardized mean difference (SMD) and using RevMan 5.3 software (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, 2014). Results: The meta-analysis showed that blood flow restriction training increased the lower limb extensor muscle strength [SMD = 0.72, 95%; confidence interval (CI): 0.43 to 1.00, p < 0.01], knee extensor isokinetic torque SMD = 0.48 [95% CI: 0.24 to 0.73, p < 0.01], knee flexor isokinetic torque SMD = 0.39 [95% CI: 0.11 to 0.67, p < 0.01], and squat one-repetition maximum [SMD = 0.28, 95% CI: 0.01 to 0.55, p < 0.01]. There was no publication bias. Evaluation of dose-response relationship showed that the training load, mode, frequency, duration, and maximum cuff pressure affected the muscle function. Conclusion: blood flow restriction training. 16 significantly improved lower limb muscle strength, and the optimal training conditions consisted of a weight load smaller or equal to 30% of one-repetition maximum, training duration longer than 4 weeks, frequency of more than 3 times/week, and maximum cuff pressure lower than 200 mmHg. Systematic Review Registration: website, identifier registration number.

[Research on parameters optimization of laser-induced breakdown spectroscopy based experimental device].

For a better application of laser-induced breakdown spectroscopy (LIBS) to coal quality analysis, it is necessary to optimize the key parameters of the experimental LIBS-based device. The relationships between the key parameters and the signal-to-noise ratios (S/N) of the elemental emission lines in the plasma spectrum of the pulverized coal were studied, according to which the optimal parameters can be selected. Experimental results indicate that the optimal settings for our LIBS-based device are laser pulse energy = 120 mJ x Pulse(-1), delay time of spectrometer = 200 ns, laser focal point be located 3-5 mm underneath the sample surface, rotation speed of sample cell = 2.7 rev x min(-1), a narrow-band filter with center frequency of 1 064 nm and a diaphragm with center hole diameter of 1.5 mm be placed in the path of the laser beam. Quantitative analysis results of pulverized coal show that, by using the optimal LIBS-based device, the standard deviation (SD) of C has been reduced from 6.7% to 1.6%, while the relative standard deviation (RSD) of other trace elements has been reduced from 28% to 10%. As a result, th accuracy has been improved greatly.

[Spatio-temporal Distribution Characteristics and Driving Factors of Zooplankton in Hongze Lake].

Hongze Lake is the fourth largest freshwater lake in China and is an important source of water for surrounding industrial and agricultural processes and fishery resources. Analyzing the changes in the zooplankton community structure in Hongze Lake can provide scientific support for the scientific management of its ecology and environment. A one-year monthly monitoring study was conducted from March 2017 to February 2018 to analyze the temporal and spatial changes in species composition, density, and biomass of zooplankton in Hongze Lake, as well as the seasonal changes in community diversity and dominant species. Canonical correspondence analysis was employed to explore the relationships between the temporal and spatial changes in zooplankton and the environmental factors of Hongze Lake. The results showed that the average annual density of zooplankton in Hongze Lake was 383.87 ind ·L-1, and the average annual biomass was 1.36 mg ·L-1. The community structure of zooplankton in Hongze Lake varied greatly across time and space. Community structure varied greatly in summer, and zooplankton density and biomass reached a maximum in autumn. The community structure of the zooplankton was the simplest in winter. Chengzi Bay and Lihewa Bay exhibited an abundance of many different zooplankton species with limited spatial differentiation, whereas the zooplankton in the overflow area comprised fewer species but exhibited greater spatial variation. In summer, water level and temperature are the dominant factors, whereas in autumn and winter, the dominant factors are water temperature, nutrients, and chlorophyll. Canonical correspondence analysis showed that the temporal and spatial changes in zooplankton community structure in Hongze Lake were mainly determined by water level, total phosphorus, water temperature, and total nitrogen content. Water level fluctuation has the greatest direct impact on zooplankton community structure, and water quality regulation has indirect impact.

Targeted Blood Brain Barrier Opening With Focused Ultrasound Induces Focal Macrophage/Microglial Activation in Experimental Autoimmune Encephalomyelitis.

Experimental autoimmune encephalomyelitis (EAE) is a model of multiple sclerosis (MS). EAE reflects important histopathological hallmarks, dissemination, and diversity of the disease, but has only moderate reproducibility of clinical and histopathological features. Focal lesions are less frequently observed in EAE than in MS, and can neither be constrained to specific locations nor timed to occur at a pre-specified moment. This renders difficult any experimental assessment of the pathogenesis of lesion evolution, including its inflammatory, degenerative (demyelination and axonal degeneration), and reparatory (remyelination, axonal sprouting, gliosis) component processes. We sought to develop a controlled model of inflammatory, focal brain lesions in EAE using focused ultrasound (FUS). We hypothesized that FUS induced focal blood brain barrier disruption (BBBD) will increase the likelihood of transmigration of effector cells and subsequent lesion occurrence at the sonicated location. Lesion development was monitored with conventional magnetic resonance imaging (MRI) as well as with magnetic resonance elastography (MRE) and further analyzed by histopathological means. EAE was induced in 12 6-8 weeks old female C57BL/6 mice using myelin oligodendrocyte glycoprotein (MOG) peptide. FUS-induced BBBD was performed 6, 7, and 9 days after immunization in subgroups of four animals and in an additional control group. MRI and MRE were performed on a 7T horizontal bore small animal MRI scanner. Imaging was conducted longitudinally 2 and 3 weeks after disease induction and 1 week after sonication in control animals, respectively. The scan protocol comprised contrast-enhanced T1-weighted and T2-weighted sequences as well as MRE with a vibration frequency of 1 kHz. Animals were sacrificed for histopathology after the last imaging time point. The overall clinical course of EAE was mild. A total of seven EAE animals presented with focal T2w hyperintense signal alterations in the sonicated hemisphere. These were most frequent in the group of animals sonicated 9 days after immunization. Histopathology revealed foci of activated microglia/macrophages in the sonicated right hemisphere of seven EAE animals. Larger cellular infiltrates or apparent demyelination were not seen. Control animals showed no abnormalities on MRI and did not have clusters of activated microglia/macrophages at the sites targeted with FUS. None of the animals had hemorrhages or gross tissue damage as potential side effects of FUS. EAE-animals tended to have lower values of viscoelasticity and elasticity in the sonicated compared to the contralateral parenchyma. This trend was significant when comparing the right sonicated to the left normal hemisphere and specifically the right sonicated compared to the left normal cortex in animals that underwent FUS-BBBD 9 days after immunization (right vs. left hemisphere: mean viscoelasticity 6.1 vs. 7.2 kPa; p = 0.003 and mean elasticity 4.9 vs. 5.7 kPa, p = 0.024; right vs. left cortex: mean viscoelasticity 5.8 vs. 7.5 kPa; p = 0.004 and mean elasticity 5 vs. 6.5 kPa; p = 0.008). A direct comparison of the biomechanical properties of focal T2w hyperintensities with normal appearing brain tissue did not yield significant results. Control animals showed no differences in viscoelasticity between sonicated and contralateral brain parenchyma. We here provide first evidence for a controlled lesion induction model in EAE using FUS-induced BBBD. The observed lesions in EAE are consistent with foci of activated microglia that may be interpreted as targeted initial inflammatory activity and which have been described as pre-active lesions in MS. Such foci can be identified and monitored with MRI. Moreover, the increased inflammatory activity in the sonicated brain parenchyma seems to have an effect on overall tissue matrix structure as reflected by changes of biomechanical parameters.

Observed Effects of Whole-Brain Radiation Therapy on Focused Ultrasound Blood-Brain Barrier Disruption.

As focused ultrasound for blood-brain barrier disruption (FUS-BBBD) has progressed to human application, it has become necessary to consider the potential effects of prior irradiation treatments. Using a murine model, we examined the effects of whole-brain irradiation on FUS-BBBD. We first subjected half of the experimental cohort to daily 3-Gy whole-brain irradiation for 10 consecutive days. Then, microbubble-assisted FUS-BBBD was performed unilaterally while the contralateral sides served as unsonicated controls. FUS-BBBD, as evident by measuring the fluorescence yield of extravasated trypan blue dye, was identified at all sites with minimal or no apparent pathology. The peak fluorescence intensity caused by extravasated dye in the sonicated region was 17.5 ± 12.1% higher after radiation and FUS-BBBD than after FUS-BBBD alone, suggesting that prior radiation of the brain may be a sensitizing factor for FUS-BBBD. Radiation alone-without FUS-BBBD-resulted in mild BBB disruption. Hemorrhagic petechiae were observed in 9 of 12 radiated brains, with 77% of them clearly located outside the sonicated area; no petechiae were found in non-irradiated animals. This radiation protocol did not appear to increase the risk for vascular damage associated with FUS-BBBD.

Direct Activation of Cortical Neurons in the Primary Somatosensory Cortex of the Rat in Vivo Using Focused Ultrasound.

We address the recent controversy over whether focused ultrasound (FUS) activates cortical neurons directly or indirectly by initially activating auditory pathways. We obtained two types of evidence that FUS can directly activate cortical neurons. The depth profile of the local field potential (LFP) in the barrel cortex of the rat in vivo indicated a generator was located within the cortical gray matter. The onset and peak latencies of the initial component p1 were 3.2 ± 0.25 ms (mean ± standard error of the mean) and 7.6 ± 0.12 ms, respectively, for the direct cortical response (DCR), 6.8 ± 0.40 and 14.3 ± 0.54 ms for the FUS-evoked LFP (4 MHz, 3.2 MPa, 50 or 300 µs/pulse, 1-20 pulses at 1 kHz) and 6.9 ± 0.51 and 15.8 ± 0.94 ms for the LFP evoked by 1-ms deflection of the C2 whisker projecting to the same area. The peak latency of the FUS p1 was statistically (t-test) longer than the DCR, but shorter than the whisker p1 at p < 0.005.

MRI Monitoring and Quantification of Ultrasound-Mediated Delivery of Liposomes Dually Labeled with Gadolinium and Fluorophore through the Blood-Brain Barrier.

Magnetic resonance image-guided focused ultrasound has emerged as a viable non-invasive technique for the treatment of central nervous system-related diseases/disorders. Application of mechanical and thermal effects associated with focused transcranial ultrasound has been studied extensively in pre-clinical models, which has paved the way for clinical trials. However, in vivo treatment evaluation techniques on drug delivery application via blood-brain barrier opening has not been fully explored. Current treatment evaluation techniques via magnetic resonance imaging are hindered by systemic toxicity resulting from free gadolinium delivery. Here we propose a novel treatment evaluation strategy to overcome limitations by (i) synthesizing liposomes that are dually labeled with gadolinium, a magnetic resonance imaging (MRI) contrast agent, and rhodamine, a fluorophore; (ii) applying a focused ultrasound (FUS)-mediated BBB opening technique to deliver the liposomes across vascular barriers, achieving local gadolinium enhancement while reducing systemic and unwanted regional toxic effects associated with free gadolinium; and (iii) utilizing the MRI modality to confirm the delivery as it is already included in the FUS treatment in clinic. Liposomes were secondarily labeled with a fluorescent marker to confirm results obtained by MRI quantification postmortem. Two different sizes, 77.5 nm (group A) and 140 nm (group B), of gadolinium- and fluorescence-labeled liposomes were fabricated using thin-film hydration followed by extrusion methods and determined their stability up to 6 h under physiologic conditions. Gadolinium signal was detected on contrast-enhanced T1-weighted MRI 5 h after the delivery of liposomes via the BBB opening approach with an ultrasound pulse of 0.42 MPa (estimate in water) combined with microbubbles. MRI contrast was enhanced significantly in sonicated regions compared with non-sonicated regions of the brain. This was due to the accumulation of labeled liposomes, which was confirmed by detection of rhodamine fluorescence in histologic sections. The relative increase in MRI signal intensity was greater for smaller liposomes (mean diameter = 77.5 nm) than larger liposomes (mean diameter = 140 nm), which suggested a greater accumulation of the smaller liposomes in the brain after ultrasound-mediated opening of the BBB. Our findings suggest that the dual-labeled nanocarrier platform can be established, the FUS-mediated BBB opening approach can be used to deliver it through vascular barriers and MRI can be used to evaluate the extent of nanocarrier delivery.

Evaluation of permeability, doxorubicin delivery, and drug retention in a rat brain tumor model after ultrasound-induced blood-tumor barrier disruption.

Drug delivery in brain tumors is challenging because of the presence of blood-brain barrier (BBB) and the blood-tumor barrier (BTB). Focused ultrasound (FUS) combined with microbubbles can enhance the permeability of the BTB in brain tumors, as well as disrupting the BBB in the surrounding tissue. In this study, dynamic contrast-enhanced Magnetic Resonance Imaging (DCE-MRI) was used to characterize FUS-induced permeability changes in a rat glioma model and in the normal brain and to investigate the relationship between these changes and the resulting concentration of the chemotherapy agent doxorubicin (DOX). 9L gliosarcoma cells were implanted in both hemispheres in male rats. At day 10-12 after implantation, FUS-induced BTB disruption using 690kHz ultrasound and Definity microbubbles was performed in one of the tumors and in a normal brain region in each animal. After FUS, DOX was administered at a dose of 5.67mg/kg. The resulting DOX concentration was measured via fluorometry at 1 or 24h after FUS. The transfer coefficient Ktrans describing extravasation of the MRI contrast agent Gd-DTPA was significantly increased in both the sonicated tumors and in the normal brain tissue (P<0.001) between the two DCE-MRI acquisitions obtained before and after FUS, while no significant difference was found in the controls (non-sonicated tumor/normal brain tissue). DOX concentrations were also significantly larger than controls in both the sonicated tumors and in the normal tissue volumes at 1 and 24h after sonication. The DOX concentrations were significantly larger (P<0.01) in the control tumors harvested 1h after FUS than in those harvested at 24h, when the tumor concentrations were not significantly different than in the non-sonicated normal brain. In contrast, there was no significant difference in the DOX concentrations between the tumors harvested at 1 and 24h after FUS or in the concentrations measured in the brain at these time points. The transfer coefficient Ktrans for Gd-DTPA and the drug concentrations showed a good linear correlation (R2=0.56). Overall, these data suggest that FUS and microbubbles can not only increase DOX delivery across the BBB and BTB, but that it is retained in the tissue at significantly enhanced levels for at least 24h. Such enhanced retention may increase the potency of this chemotherapy agent and allow for reduced systemic doses. Furthermore, MRI-based estimates of Gd-DTPA transport across these barriers might be useful to estimate local DOX concentrations in the tumor and in the surrounding normal tissue.

Effects on P-Glycoprotein Expression after Blood-Brain Barrier Disruption Using Focused Ultrasound and Microbubbles.

Many blood-borne substances attempting to pass through the luminal membrane of brain endothelial cells are acted upon by a variety of metabolizing enzymes or are actively expelled back into the capillary lumen by embedded efflux transporters, such as Permeability-glycoprotein (Pgp). Overexpression of this protein has also been linked to multidrug resistance in cancer cells. Previous studies have shown that focused ultrasound (FUS), when combined with a microbubble agent, has ability to temporarily disrupt blood-brain barrier (BBBD). In this work, we investigated whether modulation of Pgp expression is part of the FUS-induced effects. We found that ultrasound can temporarily suppress Pgp expression. When BBBD was produced at 0.55 MPa, Pgp was suppressed up to 48 hours and restored by 72 hours. At 0.81 MPa, suppression can last 72 hours or longer. These findings support the idea that microbubble-enhanced FUS disrupts the functional components of the BBB through suppression of drug efflux.

Clinical and imaging features of spinal cord type of neuro Behçet disease: A case report and systematic review.

RATIONAL: To investigate the clinical and MRI characteristics of spinal cord nerve Behçet's disease. PATIENT CONCERNS: One patient with spinal cord nerve Behçet's disease was admitted to our hospital at October 20, 2015. DIAGNOSE: Spinal cord nerve Behçet's disease. INTERVENTIONS: Retrospective analysis was performed on such case as well as 16 cases of spinal cord nerve Behçet's disease reported in China or abroad. OUTCOMES: Seventeen cases of spinal cord type of neuro Behçet's disease include 13 men and 4 women, with an average age of onset of 34.8 years old. The mean time from Behçet's disease symptoms to spinal cord involvement were 10.8 years. The initial symptom in one case was spinal cord injury, and another 4 cases had a recurrence course. The most common performance of spinal cord injury was sensory disturbance (82.4%), following by weakness (76.5%), sphincter or sexual dysfunction (58.8%), and pain in back, backside of neck or lower chest (29.4%). The number of cells was slightly increased or the protein level was increased in cerebrospinal fluid test. And the water channel protein antibody and oligoclonal band of serum levels were all negative. The spinal cord injury involved more than 3 vertebral bodies in 10 cases, and involved more than half of spinal cord in sagittal plane in 8 cases. In acute stage, shock therapy with large dose of glucocorticoid was generally applied both in China and abroad. LESSONS: The clinical features of spinal cord nerve Behçet's disease were various, making it easily misdiagnosed. Longitudinal extensive transverse myelitis performs as a characteristic manifestation.

Brain arterioles show more active vesicular transport of blood-borne tracer molecules than capillaries and venules after focused ultrasound-evoked opening of the blood-brain barrier.

Previously, activation of vesicular transport in the brain microvasculature was shown to be one of the mechanisms of focused ultrasound-induced blood-brain barrier (BBB) opening. In the present study, we aimed to estimate the rate of the transendothelial vesicular traffic after focused ultrasound sonication in the rabbit brain, using ultrastructural morphometry and horseradish peroxidase (HRP) as a tracer. In the capillaries, the mean endothelial pinocytotic densities (the number of HRP-containing vesicles per microm(2) of the cell cytoplasm) were 0.9 and 1.05 vesicles/microm(2) 1 h after sonication with ultrasound frequencies of 0.69 and 0.26 MHz, respectively. In the arterioles, these densities were 1.63 and 2.43 vesicles/microm(2), values 1.8 and 2.3 times higher. In control locations, the densities were 0.7 and 0.14 vesicles/microm(2) for capillaries and arterioles, respectively. A small number of HRP-positive vesicles were observed in the venules. Focal delivery of HRP tracer was also observed in light microscopy. The results indicate that the precapillary microvessels play an important role in macromolecular transcytoplasmic traffic through the ultrasound-induced BBB modulation, which should be considered in the future development of trans-BBB drug delivery strategies.

[The anatomical characteristics and its applied significance of laparoscopic rectal surgery].

OBJECTIVE: To realize the anatomical characteristics of laparoscopic rectum surgery and its clinical significance. METHODS: 117 cases with benign and malignant diseases of rectum were operated by laparoscopic methods. The anatomy closely related with operation was analyzed. RESULTS: The median operative time were 144 min. 4 cases were converted to open operations, so the converted rate was 1.7%. The blood loss in operation was rather little with an average of 126 ml. No instant or delayed injury of ureters, large bleeding in front of sacrum and other operation-related severe complications happened intra- and after operation. Dissecting only in one case disrupted the anterior-left wall of rectum. CONCLUSION: Laparoscopic rectal surgery is clinically feasible. Mastering the anatomical characteristics of laparoscopic rectum surgery can make us reduce the operative mistakes and complications.

[Study on the relationship between aspirin resistance and incidence of myonecrosis after non-emergent percutaneous coronary intervention].

OBJECTIVE: To investigate the occurrence of aspirin resistance in coronary heart disease (CHD) patients and its influence on myonecrosis among patients undergoing non-emergent percutaneous coronary intervention (PCI). METHODS: 256 CHD patients who have been on aspirin (100 mg/d) for at least 7 days were recruited based on aspirin responsiveness determination. All the patients were divided into two groups: aspirin-resistant group and aspirin-sensitive group. For all patients scheduled for non-emergent PCI, a loading dose of 300 mg of clopidogrel was given at least 12 h before PCI and a 75 mg maintenance dose was given every morning before and after PCI. The incidence of myonecrosis was evaluated by the levels of creatine kinase-myocardial band (CK-MB) and troponin I (TnI) before and after PCI. RESULTS: Aspirin resistance was found in 67 (26.2%) patients and 189 (73.8%) patients were aspirin-sensitive. There was a significantly higher proportion of female subjects in the aspirin-resistant group. The incidence of any CK-MB elevation was 38 (56.7%) in aspirin-resistant group and 42 (22.2%) in aspirin-sensitive group (P < 0.01). The elevation of TnI was observed in 41 (61.2%) of the aspirin-resistant group and in 67 (35.4%) of the aspirin-sensitive group (P < 0.05). Multivariate analysis revealed that aspirin resistance was an independent predictor for CK-MB elevation after PCI (OR = 2.5; 95% CI 1.5 to 6.5; P < 0.05). CONCLUSION: Aspirin resistance exists in some CHD patients, which increases the risk of myonecrosis following non-emergent PCI.

Multiple sessions of liposomal doxorubicin delivery via focused ultrasound mediated blood-brain barrier disruption: a safety study.

Transcranial MRI-guided focused ultrasound is a rapidly advancing method for delivering therapeutic and imaging agents to the brain. It has the ability to facilitate the passage of therapeutics from the vasculature to the brain parenchyma, which is normally protected by the blood-brain barrier (BBB). The method's main advantages are that it is both targeted and noninvasive, and that it can be easily repeated. Studies have shown that liposomal doxorubicin (Lipo-DOX), a chemotherapy agent with promise for tumors in the central nervous system, can be delivered into the brain across BBB. However, prior studies have suggested that doxorubicin can be significantly neurotoxic, even at small concentrations. Here, we studied whether multiple sessions of Lipo-DOX administered after FUS-induced BBB disruption (FUS-BBBD) induces severe adverse events in the normal brain tissues. First, we used fluorometry to measure the doxorubicin concentrations in the brain after FUS-BBBD to ensure that a clinically relevant doxorubicin concentration was achieved in the brain. Next, we performed three weekly sessions with FUS-BBBD±Lipo-DOX administration. Five to twelve targets were sonicated each week, following a schedule described previously in a survival study in glioma-bearing rats (Aryal et al., 2013). Five rats received three weekly sessions where i.v. injected Lipo-DOX was combined with FUS-BBBD; an additional four rats received FUS-BBBD only. Animals were euthanized 70days from the first session and brains were examined in histology. We found that clinically-relevant concentrations of doxorubicin (4.8±0.5µg/g) were delivered to the brain with the sonication parameters (0.69MHz; 0.55-0.81MPa; 10ms bursts; 1Hz PRF; 60s duration), microbubble concentration (Definity, 10µl/kg), and the administered Lipo-DOX dose (5.67mg/kg) used. The resulting concentration of Lipo-DOX was reduced by 32% when it was injected 10min after the last sonication compared to cases where the agent was delivered before sonication. In histology, the severe neurotoxicity observed in some previous studies with doxorubicin by other investigators was not observed here. However, four of the five rats who received FUS-BBBD and Lipo-DOX had regions (dimensions: 0.5-2mm) at the focal targets with evidence of minor prior damage, either a small scar (n=4) or a small cyst (n=1). The focal targets were unaffected in rats who received FUS-BBBD alone. The result indicates that while delivery of Lipo-DOX to the rat brain might result in minor damage, the severe neurotoxicity seen in earlier works does not appear to occur with delivery via FUS-BBB disruption. The damage may be related to capillary damage produced by inertial cavitation, which might have resulted in excessive doxorubicin concentrations in some areas.

Enhancement in blood-tumor barrier permeability and delivery of liposomal doxorubicin using focused ultrasound and microbubbles: evaluation during tumor progression in a rat glioma model.

Effective drug delivery to brain tumors is often challenging because of the heterogeneous permeability of the 'blood tumor barrier' (BTB) along with other factors such as increased interstitial pressure and drug efflux pumps. Focused ultrasound (FUS) combined with microbubbles can enhance the permeability of the BTB in brain tumors, as well as the blood-brain barrier in the surrounding tissue. In this study, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was used to characterize the FUS-induced permeability changes of the BTB in a rat glioma model at different times after implantation. 9L gliosarcoma cells were implanted in both hemispheres in male rats. At day 9, 14, or 17 days after implantation, FUS-induced BTB disruption using 690 kHz ultrasound and definity microbubbles was performed in one tumor in each animal. Before FUS, liposomal doxorubicin was administered at a dose of 5.67 mg kg(-1). This chemotherapy agent was previously shown to improve survival in animal glioma models. The transfer coefficient Ktrans describing extravasation of the MRI contrast agent Gd-DTPA was measured via DCE-MRI before and after sonication. We found that tumor doxorubicin concentrations increased monotonically (823 ± 600, 1817 ± 732 and 2432 ± 448 ng g(-1)) in the control tumors at 9, 14 and 17 d. With FUS-induced BTB disruption, the doxorubicin concentrations were enhanced significantly (P < 0.05, P < 0.01, and P < 0.0001 at days 9, 14, and 17, respectively) and were greater than the control tumors by a factor of two or more (2222 ± 784, 3687 ± 796 and 5658 ± 821 ng g(-1)) regardless of the stage of tumor growth. The transfer coefficient Ktrans was significantly (P < 0.05) enhanced compared to control tumors only at day 9 but not at day 14 or 17. These results suggest that FUS-induced enhancements in tumor drug delivery are relatively consistent over time, at least in this tumor model. These results are encouraging for the use of large drug carriers, as they suggest that even large/late-stage tumors can benefit from FUS-induced drug enhancement. Corresponding enhancements in Ktrans were found to be variable in large/late-stage tumors and not significantly different than controls, perhaps reflecting the size mismatch between the liposomal drug (~100 nm) and Gd-DTPA (molecular weight: 938 Da; hydrodynamic diameter: ≃2 nm). It may be necessary to use a larger MRI contrast agent to effectively evaluate the sonication-induced enhanced permeabilization in large/late-stage tumors when a large drug carrier such as a liposome is used.

[Mastoscopic extirpation of benign breast masses by small and concealing incision].

OBJECTIVE: To investigate the feasibility and effect of the mastoscopic extirpation of benign breast masses by small and concealing incision. METHODS: 72 benign breast masses of 64 patients were mastoscopically extirpated. Transaxillary and transareolar small incisions were selected under local and vein analgesia anaesthesia. RESULTS: Most of patients were operated in clinic, only 28 patients in hospital. The average operation time was 46.1 minutes. The sensation and erection of breast nipples were normal in all patients. 2 patients with the more obvious complications (one with skin burned by electric scalpel, another with wide subcutaneous ecchymosis) complained this kind of operation, other patients were greatly satisfied with the cosmetic outcome of the operation. CONCLUSIONS: The mastoscopic extirpation of benign breast masses by small and concealing incision can be completed in most of the patients under local anesthesia. The incision is small and concealing, which raises the quality of life of the patients. This operation procedure meets the needs of wide women on the treatment of breast disease to a great extent and also alters the routine conception of the excision of benign breast mass.