Direct in Situ Fabrication of Multicolor Afterglow Carbon Dot Patterns with Transparent and Traceless Features via Laser Direct Writing.

Multicolor afterglow patterns with transparent and traceless features are important for the exploration of new functionalities and applications. Herein, we report a direct in situ patterning technique for fabricating afterglow carbon dots (CDs) based on laser direct writing (LDW) for the first time. We explore a facile step-scanning method that reduces the heat-affected zone and avoids uneven heating, thus producing a fine-resolution afterglow CD pattern with a minimum line width of 80 µm. Unlike previous LDW-induced luminescence patterns, the patterned CD films are traceless and transparent, which is mainly attributed to a uniform heat distribution and gentle temperature rise process. Interestingly, by regulating the laser parameters and CD precursors, an increased carbonization and oxidation degree of CDs could be obtained, thus enabling time-dependent, tunable afterglow colors from blue to red. In addition, we demonstrate their potential applications in the in situ fabrication of flexible and stretchable optoelectronics.

Contrast-enhanced sonography for detection of secondary lymph nodes in a melanoma tumor animal model.

OBJECTIVES: To investigate the use of contrast-enhanced ultrasound imaging (US) for detection of secondary lymph nodes (LNs) in a naturally occurring melanoma swine model compared to surgery and pathologic assessment. METHODS: Twenty-seven Sinclair swine were studied. The perfluorobutane microbubble contrast agent Sonazoid (GE Healthcare, Oslo, Norway) was administered (1.0 mL total dose) around the melanoma, and contrast-enhanced US was used to localize contrast-enhanced sentinel lymph nodes (SLNs). Then Sonazoid (dose, 0.25-1.0 mL) was injected into the SLNs to detect contrast-enhanced efferent lymphatic channels and secondary LNs. After peritumoral injection of blue dye, a surgeon (blinded to the contrast-enhanced US results) performed a radical LN dissection. Contrast-enhanced US was used to guide removal of any enhanced secondary LNs left after radical LN dissection. Clustered conditional logistic regression analyzed the benefit of contrast-enhanced US-directed secondary LN dissection over radical LN dissection using pathologic findings as the reference standard. RESULTS: A total of 268 secondary LNs were resected, with 59 (22%) containing metastases. Contrast-enhanced US detected 92 secondary LNs; 248 were identified by radical LN dissection; and 68 were identified by both methods. Metastases were detected in 20% (51 of 248) and 40% (37 of 92) of the secondary LNs identified by radical LN dissection and contrast-enhanced US, respectively. Thus, secondary LNs detected by contrast-enhanced US were nearly 5 times more likely to contain metastases than secondary LNs removed by radical LN dissection (odds ratio, 4.8; P < .0001). Twenty-two of the 180 secondary LNs (12%) identified only by radical LN dissection contained metastases, whereas contrast-enhanced US identified 20 secondary LNs after the surgeon completed the radical LN dissection, of which 8 (40%) contained metastases. CONCLUSIONS: Secondary LNs can be detected by using contrast-enhanced US after injection of Sonazoid into SLNs. Secondary LNs detected with contrast-enhanced US are significantly more likely to contain metastases than those removed by radical LN dissection.

[Clinical study of Fuzheng Yiliu Recipe combined with microwave ablation on hepatocellular carcinoma].

OBJECTIVE: To explore the clinical value of Fuzheng Yiliu Recipe (FYR) combined with microwave ablation on hepatocellular carcinoma. METHODS: Sixty patients with hepatocellular carcinoma were randomly assigned to the control group and the treatment group according to the random digit table, 30 in each group. Patients in the control group received microwave ablation therapy, while those in the treatment group received FYR three days after microwave ablation. The therapeutic course was 6 months. By the end of the treatment, the short-term objective therapeutic efficacy, the liver function, the hepatic fibrosis index, the cellular immune function were statistically analyzed between the two groups. RESULTS: The indices of the liver function, the hepatic fibrosis, and the cellular immune function were more significantly improved in the treatment group than in the control group (P < 0.05). The CD4+ level and the ratio of CD4+/CD8+ of the treatment group were remarkably higher than those of the control group (40.38 +/- 12.47 vs 28. 19 +/- 6.59, 1.49 +/- 0.41 vs 1.22 +/- 0.31). The tubercle recurrence rate of the treatment group (14.0%, 7/50) was significantly lower than that of the control group (33.3%, 15/45) after 6 months of treatment (P < 0.05). CONCLUSION: FYR combined with microwave ablation could elevate the therapeutic efficacy, enhance the patients' immunity, improve the liver function and the hepatic fibrosis degree.

[Visual acupotomy intervention mitigates pain reaction by improving intervertebral disc degeneration and inhibiting apoptosis of nucleus pulposus cells in rabbits with cervical spondylosis].

OBJECTIVE: To investigate the effect of visual acupotomy intervention on intervertebral disc degeneration, nucleus pulposus cell apoptosis and expression of apoptosis related proteins in rabbits with cervical spondylosis (CS), so as to explore its mechanism underlying improvement of CS. METHODS: A total of 48 male New Zealand rabbits were randomly divided into blank control, model, acupotomy and medication (meloxicam) groups, with 12 rabbits in each group. The neck type CS model was established by forcing the rabbit to make a neck flexion for 5 hours in a restrained chamber, once daily for 12 weeks. Rabbits of the medication group received an intramuscular injection of meloxicam (0.35 mg/kg), once daily for 4 consecutive weeks, and those of the acupotomy group received ultrasound-guided acupotomy intervention, once a week for 4 weeks. The pain threshold (PT) was measured by using a VonFrey electronic pain detector. The levels of prostaglandin E2 (PGE2), 5-hydroxytryptamine (5-HT) and substance P (SP) in serum were detected by ELISA. The severity of intervertebral disc degeneration was observed by using magnetic resonance imaging (MRI) and given scores in accordance with Suzuki's and colleague's "new classification system of cervical disk degeneration". The apoptosis of nucleus pulposus cells was analyzed by TUNEL staining. The protein expression levels of apoptosis-related protein Fas, cysteinyl aspartate-specific protease-3 (Caspase-3), B-cell lymphoma-2 asso-ciated X protein (Bax) and B-cell lymphoma-2 protein (Bcl-2) were measured by Western blot. RESULTS: Compared with the blank control group, the PT and Bcl-2 expression and MRI score were significantly down-regulated (P<0.01, P<0.001), whereas the contents of serum PGE2, 5-HT and SP, ratios of TUNEL-positive cells, and expression of Fas, Caspase-3 and Bax were considerably up-regulated (P<0.001, P<0.05, P<0.01) in the model group. In contrast to the model group, both the medication and acupotomy groups had an obvious increase in the levels of PT and Bcl-2 expression and MRI score (P<0.05, P<0.01), and a significant decrease in the contents of serum PGE2, 5-HT, SP, ratios of TUNEL-positive cells, and expression of Fas, Caspase-3 and Bax proteins (P<0.05). No significant differences were found between the medication and acupotomy groups in all the indexes mentioned above (P>0.05). CONCLUSION: Visual acupotomy intervention can mitigate the pain state of CS rabbits, which may be related to its functions in improving the intervertebral disc degeneration, reducing inflammatory reactions and apoptosis of nucleus pulposus cells.

Evaluation of eight-style Tai chi on cognitive function in patients with cognitive impairment of cerebral small vessel disease: study protocol for a randomised controlled trial.

INTRODUCTION: Cerebral small vessel disease (CSVD) is a critical factor that causes cognitive decline and progresses to vascular dementia and acute cerebrovascular events. Tai chi has been proven to improve nerve plasticity formation and directly improve cognitive function compared with other sports therapy, which has shown its unique advantages. However, more medical evidence needs to be collected in order to verify that Tai chi exercises can improve cognitive impairment due to CSVD. The main purposes of this study are to investigate the effect of Tai chi exercise on neuropsychological outcomes of patients with cognitive impairment related to CSVD and to explore its mechanism of action with neuroimaging, including functional MRI (fMRI) and event-related potential (P300). METHODS AND ANALYSIS: The design of this study is a randomised controlled trial with two parallel groups in a 1:1 allocation ratio with allocation concealment and assessor blinding. A total of 106 participants will be enrolled and randomised to the 24-week Tai chi exercise intervention group and 24-week health education control group. Global cognitive function and the specific domains of cognition (memory, processing speed, executive function, attention and verbal learning and memory) will be assessed at baseline and 12 and 24 weeks after randomisation. At the same time, fMRI and P300 will be measured the structure and function of brain regions related to cognitive function at baseline and 24 weeks after randomisation. Recruitment is currently ongoing (recruitment began on 9 November 2020). The approximate completion date for recruitment is in April 2021, and we anticipate to complete the study by December 2021. ETHICS AND DISSEMINATION: Ethics approval was given by the Medical Ethics Committee of the Affiliated People's Hospital of Fujian University of Traditional Chinese Medicine (approval number: 2019-058-04). The findings will be disseminated through peer-reviewed publications and at scientific conferences. TRIAL REGISTRATION NUMBER: ChiCTR2000033176; Pre-results.

Electroacupuncture Attenuates Ischemic Brain Injury and Cellular Apoptosis via Mitochondrial Translocation of Cofilin.

OBJECTIVE: To investigate the potential mechanisms of electroacupuncture (EA) to prevent ischemic stroke. METHODS: The method of middle cerebral artery occlusion (MCAO) was employed to establish a rat model of ischemic stroke. Seventy-eight Sprague-Dawley rats were divided into the sham group, MCAO + EA control (EC) group, and MCAO + EA (EA) group according to a random number table (n=26 per group). EA was applied to the acupoints of Baihui (DU 20) and Shenting (DU 24) 5 min and 6 h, respectively after the onset of MCAO. Rats in the sham and EC groups received only light isoflurane anesthesia for 30 min after MCAO. The neuroprotective effects of EA were evaluated by rota-rod test, neurological deficit scores and infarct volumes. Additionally, Nissl staining and immunostaining were performed to examine brain damage, rod formation, cellular apoptosis, and neuronal loss induced by ischemia. The activities of caspase-3, and expression levels of cofilin and p-cofilin in mitochondria and cytoplasm after ischemic injury were determined by Western blot. RESULTS: Compared with the EC group, EA significantly improved neuromotor function and cognitive ability after ischemic stroke (P<0.05 or P<0.01). Therapeutic use of EA also resulted in a significant decrease of cofilin rod formation and microtubule-associated protein-2 (MAP2) degradation in the cortical penumbra area compared with the EC rats (P<0.01). Furthermore, Western blot analysis showed that EA stimulation significantly inhibited mitochondrial translocation of cofilin and caspase-3 cleavage (P<0.05 or P<0.01). Additionally, brain damage (infarct volume and neuropathy), cellular apoptosis and neuronal loss induced by ischemia were remarkably suppressed by EA in the cortical penumbra of rats (P<0.05 or P<0.01). CONCLUSION: EA treatment after ischemic stroke may attenuate ischemic brain injury and cellular apoptosis through the regulation of mitochondrial translocation of cofilin, a novel mechanism of EA therapy.

Detecting metastasis of lymph nodes and predicting aggressiveness in patients with breast carcinomas.

OBJECTIVE: The purpose of this study was to evaluate the contrast-enhanced ultrasonographic (CEUS) characteristics of metastatic lymph nodes (LNs) and to determine the correlation of CEUS parameters with the tumor aggressiveness in patients with breast cancer. METHODS: Real-time gray scale CEUS of axillary LNs was preoperatively performed in 51 consecutive patients with breast carcinoma who were scheduled for axillary lymph node dissection. The CEUS characteristics assessed by a direct visualization method and quantification software were compared with pathologic findings. Expression of human epidermal growth factor receptor 2 (HER-2/neu) in the primary tumor was detected by immunohistochemical analysis. Correlation analysis of CEUS parameters with HER-2/neu expression and the LN stage was performed. RESULTS: Of the LNs examined, 27 were metastatic, and 25 were diagnosed as reactive hyperplasia. Lymph nodes with metastasis were characterized by centripetal progress (66.7%) and a heterogeneous pattern (55.6%) or no or scarce perfusion (25.9%). However, LNs with nonmetastases were characterized by with centrifugal enhancement (56.0%) and a homogeneous pattern (80.0%). The difference between the hyperintense and hypointense regions was higher in metastatic LNs than nonmetastatic ones (P < .001). No significant differences were found in the arrival time, time to peak intensity, and peak intensity between the two groups. A histopathologic diagnosis could be predicted with sensitivity, specificity, and accuracy of 92.6%, 76.0%, and 84.6% respectively, by a standardized difference between maximum and minimum signal intensity (SI(max)-SI(min)) value of 28. Human epidermal growth factor receptor 2 expression and the LN histopathologic stage were significantly associated with the SI(max)-SI(min). In metastatic LNs, the relationship between the diagnostic sensitivity of CEUS and the transverse diameter of LNs remained statistically significant (P < .05). CONCLUSIONS: Noninvasive CEUS can play a role in discriminating metastatic from nonmetastatic LNs and predicting the aggressiveness in patients with breast cancer.

Low-Frequency Repetitive Transcranial Magnetic Stimulation in Patients With Poststroke Aphasia: Systematic Review and Meta-Analysis of Its Effect Upon Communication.

Objective The aim of the study was to investigate the effectiveness and safety of low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) in patients with poststroke aphasia. Method We comprehensively searched for eligible studies from 11 electronic medical databases from their inception to February 20, 2019. Randomized controlled trials reporting the effectiveness of LF-rTMS for patients with poststroke aphasia were included. The primary outcome was language ability. The secondary outcomes were functional communication and adverse events. The methodological quality of the randomized controlled trials was evaluated by the Cochrane Back Review Group Risk of Bias Assessment Criteria. Results Of the 567 records retrieved, 18 studies with a total of 536 participants were included. All the included studies were of relatively acceptable methodological quality. All studies but one used LF-rTMS + speech and language therapy (SLT), not LF-rTMS alone. The meta-analysis showed that LF-rTMS had beneficial effects for patients with aphasia after a stroke in terms of naming, repetition, comprehension, written language, and functional communication. The subgroup analyses of language performance showed positive effects of LF-rTMS among stroke patients with chronic aphasia and acute aphasia. LF-rTMS + SLT had effects on language performance that were superior to the sham rTMS + SLT and SLT alone. A shorter LF-rTMS duration benefited language performance more than a longer duration. Additionally, 20 min of LF-rTMS per session produced a positive effect on language ability for patients with aphasia after a stroke. No adverse events were reported. Conclusions LF-rTMS + SLT is an effective and safe method for patients with poststroke aphasia to improve their language performance. Additionally, the most commonly used LF-rTMS protocol for patients with aphasia after a stroke was 90% of the resting motor threshold 20 min per day, 5 days per week, for 2 weeks.

Cofilin Inhibition by Limk1 Reduces Rod Formation and Cell Apoptosis after Ischemic Stroke.

Cofilin, a cytoskeletal actin severing protein, is essential for the initiation phase of apoptosis. The formation of cofilin rods (containing 1:1 cofilin:actin) has been studied in cultured mammalian neurons under conditions of excessive glutamate, ATP depletion (ATP-D) or oxidative stress. These conditions simulate the pathologies occurring during ischemic stroke. In this study, we investigated the potential involvement of cofilin during ischemic-stroke induced apoptosis. Transient middle cerebral artery occlusion (tMCAO) was performed to establish an experimental model of ischemic stroke. We used 2,3,5-Triphenyltetrazolium Chloride (TTC) and immunostaining of the neuronal marker neuronal nuclei (NeuN) to evaluate the evolving phases of infarction in rats subjected tMCAO. Immunostaining and TdT-mediated dUTP Nick-End Labeling (TUNEL) apoptosis staining were collaboratively used to examine cofilin rod formation and cell apoptosis in response to ischemia at different time points (2 h, 8 h, 24 h and 7 d). Our results showed that infarct volume increased initially, between the first 2 h to 24 h and became stabilized 24 h to 7 d after tMCAO. The formation of cofilin rods significantly increased in the cortical core (from 2 h) and penumbra (from 8 h), peaking at 24 h and gradually diminishing 7 d after tMCAO. Progressive accumulation of cofilin rods subsequently induced microtubule-associated protein-2 (MAP2) degradation and ischemic cell apoptosis in the infarct cortex after stroke. To further corroborate the role of activated cofilin in ischemic stroke, inhibition of cofilin by LIM kinase (Limk1) over-expression was performed. Lmik1 reduced cofilin rod formation and MAP2 degradation, and consequently, attenuated cofilin mediated-apoptosis 24 h after tMCAO. From this evidence we conclude that cofilin plays a role in the onset of ischemic-induced apoptosis and may be efficacious in future studies as a drug target for ischemic stroke.

Effects of Apelin on Left Ventricular-Arterial Coupling and Mechanical Efficiency in Rats with Ischemic Heart Failure.

Apelin plays important roles in cardiovascular homeostasis. However, its effects on the mechanoenergetics of heart failure (HF) are unavailable. We attempted to investigate the effects of apelin on the left ventricular-arterial coupling (VAC) and mechanical efficiency in rats with HF. HF was induced in rats by the ligation of the left coronary artery. The ischemic HF rats were treated with apelin or saline for 12 weeks. The sham-operated animals served as the control. The left ventricular (LV) afterload and the systolic and diastolic functions, as well as the mechanoenergetic indices were estimated from the pressure-volume loops. Myocardial fibrosis by Masson's trichrome staining, myocardial apoptosis by TUNEL, and collagen content in the aorta as well as media area in the aorta and the mesenteric arteries were determined. Our data indicated that HF rats manifested an increased arterial load (Ea), a declined systolic function (reduced ejection fraction, +dP/dtmax, end-systolic elastance, and stroke work), an abnormal diastolic function (elevated end-diastolic pressure, τ, and declined -dP/dtmax), and decreased mechanical efficiency. Apelin treatment improved those indices. Concomitantly, increased fibrosis in the LV myocardium and the aorta and enhanced apoptosis in the LV were partially restored by apelin treatment. A declined wall-to-lumen ratio in the mesenteric arteries of the untreated HF rats was further reduced in the apelin-treated group. We concluded that the rats with ischemic HF were characterized by deteriorated LV mechanoenergetics. Apelin improved mechanical efficiency, at least in part, due to the inhibiting cardiac fibrosis and apoptosis in the LV myocardium, reducing collagen deposition in the aorta and dilating the resistant artery.

Acupotomy versus acupuncture for cervical spondylotic radiculopathy: protocol of a systematic review and meta-analysis.

INTRODUCTION: Cervical spondylotic radiculopathy (CSR) is the most common pattern of cervical spondylosis, which is a serious and common degenerative disease. Both acupotomy and acupuncture have been widely used clinically to treat CSR in China with satisfied efficacy. However, there is no systematic review comparing the effectiveness of these two therapies. The aim of this study is to compare the therapeutic efficacy and safety between acupotomy and acupuncture for patients with CSR to provide evidence for clinical practice. METHODS AND ANALYSIS: The following electronic databases will be searched: Web of Science, PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure , China Biology Medicine disc, Wanfang Database and Chinese Scientific Journal Database (VIP). The randomised controlled trials of acupotomy versus acupuncture with/without additional treatment for CSR will be searched in the databases from their inception to December 2018 by two researchers independently. Visual analogue scale, symptom score and neck disability index will be assessed as the primary outcomes. The total effective rate, curative rate, adverse events and amount of rescue medication used will be assessed as the secondary outcomes. The Review Manager 5.3 will be used for meta-analysis and the evidence level will be assessed by using the method for Grading of Recommendations Assessment, Development and Evaluation. Continuous outcomes will be presented as the weighted mean difference or standardised mean difference with 95% CI, whereas dichotomous data will be expressed as relative risk with 95% CI. If the included studies have existing heterogeneity (p<0.05), then a random-effects model will be used. Otherwise, we will calculate using a fixed-effects model. ETHICS AND DISSEMINATION: Ethical approval is not required because no primary data are collected. This review will be published in a peer-reviewed journal and will be presented at an international academic conference for dissemination. PROSPERO REGISTRATION NUMBER: CRD42019117348.

Warm-needle moxibustion for spasticity after stroke: A systematic review of randomized controlled trials.

BACKGROUND: Spasticity is a common post-stroke complication, and it results in substantial deterioration in the quality of life of patients. Although potential positive effects of warm-needle moxibustion on spasticity after stroke have been observed, evidence on its definitive effect remains uncertain. OBJECTIVES: This study aimed to summarize clinical evidence pertaining to therapeutic effects and safety of warm-needle moxibustion for treating spasticity after stroke. DESIGN: Randomized controlled trials were reviewed systematically on the basis of the Cochrane Handbook for Systematic Reviews of Interventions. The report follows the PRISMA statement. METHODS: Ten electronic databases (PubMed, CENTRAL, EMBASE, AMED, CINAHL, Web of Science, CBM, CNKI, WanFang, and VIP) were explored, and articles were retrieved manually from two Chinese journals (The Journal of Traditional Chinese Medicine and Zhong Guo Zhen Jiu) through retrospective search. Randomized controlled trials with warm-needle moxibustion as treatment intervention for patients with limb spasm after stroke were included in this review. The risk of bias assessment tool was utilized in accordance with Cochrane Handbook 5.1.0. All included studies reported spasm effect as primary outcome. Effect size was estimated using relative risk, standardized mean difference, or mean difference with a corresponding 95% confidence interval. Review Manager 5.3 was utilized for meta-analysis. RESULTS: Twelve randomized controlled trials with certain methodological flaws and risk of bias were included, and they involved a total of 878 participants. Warm-needle moxibustion was found to be superior to electroacupuncture or acupuncture in reducing spasm and in promoting motor function and daily living activities. Pooled results for spasm effect and motor function were significant when warm-needle moxibustion was compared with electroacupuncture or acupuncture. A comparison of daily living activities indicated significant differences between warm-needle moxibustion and electroacupuncture. However, no difference was observed between warm-needle moxibustion and acupuncture. CONCLUSIONS: Warm-needle moxibustion may be a promising intervention to reduce limb spasm as well as improve motor function and daily living activities for stroke patients with spasticity. However, evidence was not conclusive. Rigorously designed randomized controlled trials with sample sizes larger than that in the included trials should be conducted for verification.

Auricular therapy for chronic pain management in adults: A synthesis of evidence.

OBJECTIVE: To evaluate the efficacy and safety of auricular therapy (AT) on chronic pain. METHODS: A systematic review. Randomized controlled trials investigating AT for chronic pain were retrieved and RevMan 5.3 was used for meta-analysis. RESULTS: Fifteen trials were included. The overall assessment indicated that AT could be a promising intervention for chronic pain relief. Meta-analyses showed that AT decreased pain intensity, especially for chronic low back pain and chronic tension headache. The lasting effect of AT was not obvious, and it began to diminish 3 months after the completion of treatment. CONCLUSIONS: AT may positively control pain intensity for patients with chronic pain. However, due to the significant heterogeneity and methodological flaws identified in the analyzed trials, the current evidence on AT for chronic pain management is still uncertain. More rigorously designed large-scale randomized controlled trials are required to evaluate the efficacy of AT for patients with chronic pain.

Electroacupuncture ameliorates cognitive impairment and regulates the expression of apoptosis-related genes Bcl-2 and Bax in rats with cerebral ischaemia-reperfusion injury.

BACKGROUND: Post-stroke cognitive impairment seriously affects the quality of life and functional rehabilitation of patients with stroke. OBJECTIVE: To examine the effects of electroacupuncture (EA) at GV20 and GV24 on cognitive impairment and apoptosis including expression of apoptosis-related genes Bcl-2 and Bax in a rat model of cerebral ischaemia-reperfusion (IR) induced by middle cerebral artery occlusion (MCAO). METHODS: Thirty-five Sprague-Dawley rats were allocated to a sham operation control group (SC group, n=10) or underwent surgery and MCAO (n=25). Postoperatively the latter group was randomly subdivided into EA or untreated (IR) groups. Cognitive impairment was assessed using the Morris water maze (MWM). Apoptosis was examined by detection of Bcl-2 and Bax expression in the cerebral cortex. RESULTS: The EA group had significantly decreased neurological deficit scores compared to the IR group (p<0.05). In the MWM test, significant differences in escape latency and route were observed between the EA and IR groups (p<0.05). Rats in the EA group performed better in the probe trial than those in the IR group (p<0.05). EA treatment markedly reduced the number of TUNEL-positive cells compared to the IR group (20.13±4.30% vs 38.40±3.38%; p<0.001). Reverse transcription-polymerase chain reaction (RT-PCR) results showed the Bcl-2/Bax ratio was significantly increased in the EA group compared to the IR group (1.61±0.19 vs 0.50±0.05, p<0.01). CONCLUSIONS: These findings suggest that EA ameliorates cognitive impairment of rats with IR injury by modulating Bcl-2 and Bax expression.

Perfusion estimation using contrast-enhanced 3-dimensional subharmonic ultrasound imaging: an in vivo study.

OBJECTIVES: The ability to estimate tissue perfusion (in milliliter per minute per gram) in vivo using contrast-enhanced 3-dimensional (3D) harmonic and subharmonic ultrasound imaging was investigated. MATERIALS AND METHODS: A LOGIQ™ 9 scanner (GE Healthcare, Milwaukee, WI) equipped with a 4D10L probe was modified to perform 3D harmonic imaging (HI; f(transmit), 5 MHz and f(receive), 10 MHz) and subharmonic imaging (SHI; f(transmit), 5.8 MHz and f(receive), 2.9 MHz). In vivo imaging was performed in the lower pole of both kidneys in 5 open-abdomen canines after injection of the ultrasound contrast agent (UCA) Definity (Lantheus Medical Imaging, N Billerica, MA). The canines received a 5-µL/kg bolus injection of Definity for HI and a 20-µL/kg bolus for SHI in triplicate for each kidney. Ultrasound data acquisition was started just before the injection of UCA (to capture the wash-in) and continued until washout. A microvascular staining technique based on stable (nonradioactive) isotope-labeled microspheres (Biophysics Assay Laboratory, Inc, Worcester, MA) was used to quantify the degree of perfusion in each kidney (the reference standard). Ligating a surgically exposed branch of the renal arteries induced lower perfusion rates. This was followed by additional contrast-enhanced imaging and microsphere injections to measure post-ligation perfusion. Slice data were extracted from the 3D ultrasound volumes and used to generate time-intensity curves offline in the regions corresponding to the tissue samples used for microvascular staining. The midline plane was also selected from the 3D volume (as a quasi-2-dimensional [2D] image) and compared with the 3D imaging modes. Perfusion was estimated from the initial slope of the fractional blood volume uptake (for both HI and SHI) and compared with the reference standard using linear regression analysis. RESULTS: Both 3D HI and SHI were able to provide visualization of flow and, thus, perfusion in the kidneys. However, SHI provided near-complete tissue suppression and improved visualization of the UCA flow. Microsphere perfusion data were available for 4 canines (1 was excluded because of an error with the reference blood sample) and showed a mean (SD) perfusion of 9.30 (6.60) and 5.15 (3.42) mL/min per gram before and after the ligation, respectively. The reference standard showed significant correlation with the overall 3D HI perfusion estimates (r = 0.38; P = 0.007), but it correlated more strongly with 3D SHI (r = 0.62; P < 0.001). In addition, these results showed an improvement over the quasi-2D HI and SHI perfusion estimates (r = -0.05 and r = 0.14) and 2D SHI perfusion estimates previously reported by our group (r = 0.57). CONCLUSIONS: In this preliminary study, 3D contrast-enhanced nonlinear ultrasound was able to quantify perfusion in vivo. Three-dimensional SHI resulted in better overall agreement with the reference standard than 3D HI did and was superior to previously reported 2D SHI results. Three-dimensional SHI outperforms the other methods for estimating blood perfusion because of the improved visualization of the complete perfused vascular networks.

Acute portal hypertension models in dogs: low- and high-flow approaches.

Effective animal models are needed to evaluate the feasibility of new techniques to assess portal hypertension (PH). Here we developed 2 canine models of acute PH by increasing intrasinusoidal resistance and by increasing the portal vein (PV) flow volume to test the efficacy of a noninvasive technique to evaluate PH. The acute low-flow PH model was based on embolization of liver circulation by using a gelatin sponge material. The acute high-flow PH model was based on increasing the PV flow volume by using an arteriovenous (A-V) shunt from the femoral artery and saline infusion. PV pressures and diameters were assessed before and after inducing PH. Pressure values and diameters were obtained from the inferior vena cava in 3 unmanipulated controls. The low-flow model of PH was repeatable and successfully increased PV pressure by an average of 16.5 mm Hg within 15 min. The high-flow model of PH failed to achieve increased PV pressures. However, saline supplementation of the portal circulation in the high-flow model led to mean increases in PV pressures of 12.8 mm Hg within 20 min. Pulsatility in the PV was decreased in the low-flow model and increased in the high-flow model relative to baseline. No changes in PV diameter were noted in either model. These acute PH models are relatively straightforward to implement and may facilitate the evaluation of new techniques to assess PH.

Three-dimensional subharmonic ultrasound imaging in vitro and in vivo.

RATIONALE AND OBJECTIVES: Although contrast-enhanced ultrasound imaging techniques such as harmonic imaging (HI) have evolved to reduce tissue signals using the nonlinear properties of the contrast agent, levels of background suppression have been mixed. Subharmonic imaging (SHI) offers near complete tissue suppression by centering the receive bandwidth at half the transmitting frequency. The aims of this study were to demonstrate the feasibility of three-dimensional (3D) SHI and to compare it to 3D HI. MATERIALS AND METHODS: Three-dimensional HI and SHI were implemented on a Logiq 9 ultrasound scanner with a 4D10L probe. Four-cycle SHI was implemented to transmit at 5.8 MHz and receive at 2.9 MHz, while two-cycle HI was implemented to transmit at 5 MHz and receive at 10 MHz. The ultrasound contrast agent Definity was imaged within a flow phantom and the lower pole of two canine kidneys in both HI and SHI modes. Contrast-to-tissue ratios and rendered images were compared offline. RESULTS: SHI resulted in significant improvement in contrast-to-tissue ratios relative to HI both in vitro (12.11 ± 0.52 vs 2.67 ± 0.77, P< .001) and in vivo (5.74 ± 1.92 vs 2.40 ± 0.48, P = .04). Rendered 3D subharmonic images provided better tissue suppression and a greater overall view of vessels in a flow phantom and canine renal vasculature. CONCLUSIONS: The successful implementation of SHI in 3D allows imaging of vascular networks over a heterogeneous sample volume and should improve future diagnostic accuracy. Additionally, 3D SHI provides improved contrast-to-tissue ratios relative to 3D HI.

Contrast-enhanced ultrasound is helpful in the differentiation of malignant and benign breast lesions.

OBJECTIVE: To evaluate the significance of contrast-enhanced ultrasound (CEUS) examination in differential diagnosis of malignant and benign breast lesions. METHODS: Seventy-one patients with seventy-six breast tumors are selected randomly. CEUS examinations were performed before and after bolus injection of the contrast agent SonoVue (Bracco, Milan, Italy). Specific sonographic quantification software, Qontrast, was adopted to determine the morphology of vessels. Wash-in and wash-out parameters of each lesion were assessed for both procedures. RESULTS: The final histopathological findings distinguished 45 malignant and 31 benign from all of the lesions. Following SonoVue administration different perfusion phases could be identified: early (0-1min), mid (1-4min) and late (4-6min) phases. In the early phase, CEUS identified 91.1% of malignant tumors characterized by a claw-shaped enhancement, while 83.9% of benign tumors had a homogeneous enhancement, with a statistically significant difference between the two enhancement patterns (chi(2)=43.16, P<0.01). Moreover, contrast medium persistence in the late phase was helpful in the identification of benign and malignant tumors (chi(2)=46.88, P<0.01): contrast medium was present in 88.9% of malignant tumors, while in only 9.7% of the benign tumors. The study showed that various parametric imaging color maps for peak intensity and time to peak were mostly suggestive of malignancy, while quite uniform peak intensity and time to peak of color maps were the characteristic of benign tumors. The study also found that malignant lesions presented with a higher maximum intensity signal than benign ones (P<0.05) on the time-intensity curves. CONCLUSIONS: CEUS cooperating with conventional US shows improved accuracy in differentiating between malignant and benign breast tumors. It could be a reliable diagnostic method of breast lesions.