Weakly supervised real-time instance segmentation for ultrasound images of median nerves.

Medical ultrasound technology has garnered significant attention in recent years, with Ultrasound-guided regional anesthesia (UGRA) and carpal tunnel diagnosis (CTS) being two notable examples. Instance segmentation, based on deep learning approaches, is a promising choice to support the analysis of ultrasound data. However, many instance segmentation models cannot achieve the requirement of ultrasound technology e.g. real-time. Moreover, fully supervised instance segmentation models require large numbers of images and corresponding mask annotations for training, which can be time-consuming and labor-intensive in the case of medical ultrasound data. This paper proposes a novel weakly supervised framework, CoarseInst, to achieve real-time instance segmentation of ultrasound images with only box annotations. CoarseInst not only improves the network structure, but also proposes a two-stage "coarse-to-fine" training strategy. Specifically, median nerves are used as the target application for UGRA and CTS. CoarseInst consists of two stages, with pseudo mask labels generated in the coarse mask generation stage for self-training. An object enhancement block is incorporated to mitigate the performance loss caused by parameter reduction in this stage. Additionally, we introduce a pair of loss functions, the amplification loss, and the deflation loss, that work together to generate the masks. A center area mask searching algorithm is also proposed to generate labels for the deflation loss. In the self-training stage, a novel self-feature similarity loss is designed to generate more precise masks. Experimental results on a practical ultrasound dataset demonstrate that CoarseInst could achieve better performance than some state-of-the-art fully supervised works.

BMAL1/p53 mediating bronchial epithelial cell autophagy contributes to PM2.5-aggravated asthma.

BACKGROUND: Fine particulate matter (PM2.5) is associated with increased incidence and severity of asthma. PM2.5 exposure disrupts airway epithelial cells, which elicits and sustains PM2.5-induced airway inflammation and remodeling. However, the mechanisms underlying development and exacerbation of PM2.5-induced asthma were still poorly understood. The aryl hydrocarbon receptor nuclear translocator-like protein 1 (BMAL1) is a major circadian clock transcriptional activator that is also extensively expressed in peripheral tissues and plays a crucial role in organ and tissue metabolism. RESULTS: In this study, we found PM2.5 aggravated airway remodeling in mouse chronic asthma, and exacerbated asthma manifestation in mouse acute asthma. Next, low BMAL1 expression was found to be crucial for airway remodeling in PM2.5-challenged asthmatic mice. Subsequently, we confirmed that BMAL1 could bind and promote ubiquitination of p53, which can regulate p53 degradation and block its increase under normal conditions. However, PM2.5-induced BMAL1 inhibition resulted in up-regulation of p53 protein in bronchial epithelial cells, then increased-p53 promoted autophagy. Autophagy in bronchial epithelial cells mediated collagen-I synthesis as well as airway remodeling in asthma. CONCLUSIONS: Taken together, our results suggest that BMAL1/p53-mediated bronchial epithelial cell autophagy contributes to PM2.5-aggravated asthma. This study highlights the functional importance of BMAL1-dependent p53 regulation during asthma, and provides a novel mechanistic insight into the therapeutic mechanisms of BMAL1. Video Abstract.

Inter-transducer variability of ultrasound image quality in obese adults: Qualitative and quantitative comparisons.

PURPOSE: Acquiring high-quality ultrasound images of deep abdominal organs and vasculatures in obese adults (BMI >30 kg/cm2) is considered challenging. The aim of the study was to assess the inter-transducer variability in B-mode and color Doppler image quality from four commercial ultrasound transducers through qualitative and quantitative analyses. METHODS: Four curvilinear transducers on three ultrasound scanners were used to acquire B-mode and color Doppler images of deep abdominal structures in 15 obesity ≥ class II (BMI >35 kg/cm2) adults. Using visual-qualitative assessment and an offline image processing software, visual-qualitative score and quantitative mean pixel values of B-mode images, and color area ratios of color Doppler images were calculated. Differences in these values among the transducers were analyzed using one-way ANOVA. The intra- and inter-observer reliability of visual-qualitative assessment and offline image processing was tested using the intraclass correlation coefficient (ICC). RESULTS: Differences in visual-qualitative score, mean pixel value of B-mode images, and color area ratio of color Doppler images among the four transducers were significant (p < 0.001). Transducer -4 produced the highest quality of B-mode (45-53% improvement) and color Doppler (22-73% improvement) images among the transducers. Intra-observer repeatability and inter-observer reproducibility were higher with performing offline image processing than visual-qualitative assessment (ICC: 0.97-0.99 versus ICC: 0.76-0.97). CONCLUSION: There was significant image quality variability between different transducers. Transducer -4, a transducer designed specifically for high BMI patients, had the highest quality B-mode and color Doppler images compared to the other transducers lending to improved ultrasonographic visualization in obese patients.

Blockade of phosphotyrosine pathways suggesting SH2 superbinder as a novel therapy for pulmonary fibrosis.

Background: Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible fibrotic disease with high mortality. Currently, pirfenidone and nintedanib are the only approved drugs for IPF by the U.S. Food and Drug Administration (FDA), but their efficacy is limited. The activation of multiple phosphotyrosine (pY) mediated signaling pathways underlying the pathological mechanism of IPF has been explored. A Src homology-2 (SH2) superbinder, which contains mutations of three amino acids (AAs) of natural SH2 domain has been shown to be able to block phosphotyrosine (pY) pathway. Therefore, we aimed to introduce SH2 superbinder into the treatment of IPF. Methods: We analyzed the database of IPF patients and examined pY levels in lung tissues from IPF patients. In primary lung fibroblasts obtained from IPF patient as well as bleomycin (BLM) treated mice, the cell proliferation, migration and differentiation associated with pY were investigated and the anti-fibrotic effect of SH2 superbinder was also tested. In vivo, we further verified the safety and effectiveness of SH2 superbinder in multiple BLM mice models. We also compared the anti-fibrotic effect and side-effect of SH2 superbinder and nintedanib in vivo. Results: The data showed that the cytokines and growth factors pathways which directly correlated to pY levels were significantly enriched in IPF. High pY levels were found to induce abnormal proliferation, migration and differentiation of lung fibroblasts. SH2 superbinder blocked pY-mediated signaling pathways and suppress pulmonary fibrosis by targeting high pY levels in fibroblasts. SH2 superbinder had better therapeutic effect and less side-effect compare to nintedanib in vivo. Conclusions: SH2 superbinder had significant anti-fibrotic effects both in vitro and in vivo, which could be used as a promising therapy for IPF.

[Dynamic Changes of Ultrasonographic Images of Zusanli (ST 36) Region During Deqi of Acupuncture Needle Stimulation].

OBJECTIVE: To observe the dynamic changes of ultrosonographic images of Zusanli (ST 36) area during Deqi after inserting acupuncture needles, so as to provide objective evidence for clinical Deqi. METHODS: Sixty healthy volunteers (30 men and 30 women) were recruited in the present study. The subjects were asked to take a supine position on a test-bed, sterilized disposable filiform needles were perpendicularly inserted into bilateral ST 36 till Deqi (without lifting, thrusting and twirling), when, high-resolution ultrasound scanning was conducted over the regional skeletal muscles by using a radio-frequency (5-12 MHz) coil probe (Philips IU Elite Ultrasound Diagnostic Instrument) after smearing a layer of gel at the skin of ST 36. RESULTS: Among these 120 points of the 60 volunteer subjects, a marked Deqi was obtained from 108 points (consisting of 90%) including 52 points in men and 56 in women, and 53 at the left ST 36 and 56 at the right ST 36. Ultrosonographic scanning displayed that when a strongest Deqi feeling was obtained from bilateral ST 36 in these 60 volunteers, the acupuncture needle-tip was about (25.32±5.82) mm in the vertical depth, and was (5.45±0.55) mm lateral to the tibia, involving the anterior tibial muscle near the deep fascia in 46 acupoints, and the intersection fascia of anterior tibial muscle and extensor digitorum longus in 62 acupoints. CONCLUSIONS: The anterior tibial muscle near the deep fascia and the intersection fascia of anterior tibial muscle and extensor digitorum longus around ST 36 are involved in strongest Deqi. There are no significant differences in the gender and location (left and right).

Effects of Non-Focused Microbubble-Enhanced and High-Intensity Focused Ultrasound on Hemostasis in a Rabbit Model of Liver Trauma.

Uncontrolled hemorrhage after trauma to the liver can lead to death. The present study compared the effects of non-focused microbubble-enhanced ultrasound and high-intensity focused ultrasound on hepatic hemostasis in the injured liver. Blood perfusion level, serum liver enzyme levels and the aspartate transaminase/alanine transaminase ratio differed between the two types of treatment (all p values < 0.05). Hepatic cells in the microbubble-enhanced ultrasound group exhibited edema and compressed the hepatic sinus and blood vessels in the portal area. Coagulation and necrosis, inflammatory cell infiltration, and fibrous tissue encapsulation were observed in the high-intensity focused ultrasound group at later stages. The groups also differed in degree of ultrastructural damage and recovery time. Thus, microbubble-enhanced ultrasound has less of an impact on blood reperfusion and surrounding normal tissue than high-intensity focused ultrasound and is a better choice for the treatment of liver trauma.

Shear Wave Elastography of the Spleen for Monitoring Transjugular Intrahepatic Portosystemic Shunt Function: A Pilot Study.

OBJECTIVES: To assess the feasibility of splenic shear wave elastography in monitoring transjugular intrahepatic portosystemic shunt (TIPS) function. METHODS: We measured splenic shear wave velocity (SWV), main portal vein velocity (PVV), and splenic vein velocity (SVV) in 33 patients 1 day before and 3 days to 12 months after TIPS placement. We also measured PVV, SVV, and SWV in 10 of 33 patients with TIPS dysfunction 1 day before and 3 to 6 days after TIPS revision. Analyses included differences in portosystemic pressure gradient (PPG), PVV, SVV, and mean SWV before and after TIPS procedures; comparison of median SWV before and after TIPS procedures; differences in PVV, SVV, and SWV before and at different times up to 12 months after TIPS placement; accuracy of PVV, SVV, and SWV in determining TIPS dysfunction; and correlation between PPG and SWV. RESULTS: During 12 months of follow-up, 23 of 33 patients had functioning TIPS, and 10 had TIPS dysfunction. The median SWV was significantly different before and after primary TIPS placement (3.60 versus 3.05 m/s; P = .005), as well as before and after revision (3.73 versus 3.06 m/s; P = .003). The PPG, PVV, and SVV were also significantly different before and after TIPS placement and revision (P < .001). The PPG and SWV decreased, whereas PVV and SVV increased, after successful TIPS procedures. A positive correlation was observed between PPG and SWV (r = 0.70; P < .001), and a negative correlation was observed between PPG and PVV and SVV (r = -0.65; P < .001). The areas under the receiver operating characteristic curve for PVV, SVV, and SWV in determining TIPS dysfunction were 0.82, 0.84, and 0.81, respectively. CONCLUSIONS: Splenic SWV is compatible with splenoportal venous velocity in quantitatively monitoring TIPS function and determining TIPS dysfunction.

Green tagging in displaying color Doppler aliasing: a comparison to standard color mapping in renal artery stenosis.

To quantitatively assess the contrast-to-noise ratio (CNR) of green tagging and standard color flow images in displaying fast flow velocity, we retrospectively reviewed 20 cases of hemodynamically significant renal artery stenosis (RAS) detected by renal color Doppler ultrasound and confirmed with digital subtraction angiography. At the site of RAS, blood flow with high velocity that appeared as aliasing on color flow images was computationally analyzed with both green tagging and standard color mapping. To assess the difference in the CNR between normal background flow and the aliased signal as a function of visualizing aliasing between the two color mappings, we used GetColorpixels (Chongqing Medical University, Chongqing, China) to count the values in the color channels after segmenting color pixels from gray-scale pixels. We then calculated the CNR in each color channel-red, green, and blue (RGB)--in the aliasing region on green tagging and standard color mapping. The CNRs in the red, green and blue channels were 0.35 ± 0.44, 1.11 ± 0.41 and 0.51 ± 0.19, respectively, on standard color mapping, and 0.97 ± 0.80, 4.01 ± 1.36 and 0.64 ± 0.29, respectively, on green tagging. We used a single-factor analysis of variance and two-tailed t-test to assess the difference in CNR in each color channel between the two color mappings at the site of RAS. With these comparisons, there was no significant difference in the CNR in the red or blue channel between green tagging and standard color mapping (p > 0.05). However, there was a statistically significant difference in the CNR in the green channel between the two color mappings (p = 0.00019). Furthermore, the CNR measured in the green channel on the green tagging image was significantly higher than the CNRs in all other color channels on both color mapping images (p = 0.000). Hence, we conclude that green tagging has significantly higher visibility as a function of high-velocity flow than standard color mapping. The use of green tagging may improve the ability to detect RAS with color Doppler ultrasound.

Ultrasound targeted microbubble destruction promotes angiogenesis and heart function by inducing myocardial microenvironment change.

The myocardial microenvironment plays a decisive role in the survival, migration and differentiation of stem cells. We studied myocardial micro-environmental changes induced by ultrasound-targeted microbubble destruction (UTMD) and their influence on the transplantation of mesenchymal stem cells (MSCs). Various intensities of ultrasound were applied to the anterior chest in canines with myocardial infarction after intravenous injection of microbubbles. The expression of cytokines and adhesion molecules in the infarcted area of the myocardium was detected after three sessions of UTMD in 1 wk. Real-time quantitative reverse transcription polymerase chain reaction (RTQ-PCR) showed that the expression of vascular cell adhesion molecule-1 (VCAM-1), stromal cell-derived factor-1 (SDF-1) and vascular endothelial growth factor (VEGF) in the 1.5 W/cm(2) and 1 W/cm(2) groups was markedly increased compared with the 0.5 W/cm(2) or the control groups (3.8- to 4.7-fold, p < 0.01), and the expression of interleukin-1ß (IL-1ß) in the 1.5 W/cm(2) group was increased twofold over the 1.0 W/cm(2) group, whereas the 0.5 W/cm(2) group experienced no significant changes. UTMD at 1.0 W/cm(2) was performed as previously described before mesenchymal stem cell (MSC) transplantation. Myocardial perfusion, angiogenesis and heart function were investigated before and 1 month after MSC transplantation. Coronary angiography and 99mTc-tetrofosmin scintigraphy revealed that myocardial perfusion was markedly improved after UTMD + MSCs treatment (p < 0.05). At echocardiographic analysis, heart function and the wall motion score index were significantly improved by UTMD + MSCs treatment compared with MSCs or UTMD alone and the control. In a canine model of myocardial infarction, therapeutic effects were markedly enhanced by MSC transplantation after the myocardial micro-environmental changes induced by UTMD; therefore, this novel method may be useful as an efficient approach for cellular therapy.

Spleen stiffness and splenoportal venous flow: assessment before and after transjugular intrahepatic portosystemic shunt placement.

OBJECTIVES: To prospectively assess changes in spleen stiffness and splenoportal venous flow before and after transjugular intrahepatic portosystemic shunt (TIPS) placement. METHODS: We prospectively evaluated spleen stiffness measured by the mean shear wave velocity with acoustic radiation force impulse imaging and the splenoportal venous velocity with color Doppler sonography in 12 patients (mean age ± SD, 42.6 ± 11.0 years; range, 29-65 years) who underwent TIPS placement for portal hypertension and gastroesophageal bleeding. The mean shear wave velocity and angle-corrected splenoportal venous velocity at the main portal and splenic veins were measured 1 day before and 3 to 9 days after TIPS placement (mean interval, 6.0 ± 1.95 days; range, 4-10 days) and were compared with portal vein pressure measured during the procedure. RESULTS: There was a significant difference in portal vein pressure before and after TIPS (25.34 ± 6.21 versus 15.66 ± 6.07 mm Hg; P = .0005). After TIPS, the mean shear wave velocity decreased significantly in all 12 cases (3.50 ± 0.46 versus 3.15 ± 0.39 m/s before and after TIPS; P = .00015). The flow velocity at the main portal vein increased significantly after TIPS (22.21 ± 4.13 versus 47.25 ± 12.37 cm/s; P = .0000051). The splenic vein velocity and spleen index measured 25.57 ± 6.98 cm/s and 55.99 ± 21.27 cm(2), respectively, before TIPS and 35.72 ± 11.10 cm/s and 50.11 ± 21.12 cm(2) after TIPS (P = .0004 and .003). CONCLUSIONS: A significant decrease in the mean shear wave velocity and increase in the splenoportal venous velocity occurred with reduced portal vein pressure after TIPS placement. Hence, both parameters can be used as noninvasive quantitative markers for monitoring TIPS function after placement.

Liver and spleen stiffness measured by acoustic radiation force impulse elastography for noninvasive assessment of liver fibrosis and esophageal varices in patients with chronic hepatitis B.

OBJECTIVES: To evaluate the performance of liver and spleen stiffness measured by acoustic radiation force impulse (ARFI) elastography for noninvasive assessment of liver fibrosis and esophageal varices in patients with chronic hepatitis B virus. METHODS: Two hundred sixty-four participants, of whom 60 were healthy volunteers (classified as stage 0), 66 were patients with chronic hepatitis B who had undergone liver biopsy, and 138 were patients with hepatitis B-related cirrhosis, were enrolled in this study. Median liver and spleen stiffness values (meters per second) from 10 successful measurements per participant were obtained. Patients with cirrhosis were examined by upper endoscopy. RESULTS: Significant linear correlations were found between liver (Spearman ρ = 0.87; P < .001) and spleen (Spearman ρ = 0.76; P < .001) stiffness and the fibrosis stage. Liver and spleen stiffness values increased as fibrosis progressed; however, overlaps in liver stiffness were detected in stages 0 and 1 and 1 and 2, and overlaps in spleen stiffness were observed in stages 0 and 1, 1 and 2, and 2 and 3. Liver stiffness cutoff values were 1.69 m/s for predicting stage 3 or greater (area under the receiver operating characteristic curve [AUROC] = 0.99) and 1.88 m/s for stage 4 (AUROC = 0.97). The spleen stiffness cutoff value was 2.72 m/s for stage 4 (AUROC = 0.96). Liver stiffness was not correlated with the varix grade, whereas a significant linear correlation (Spearman ρ = 0.65; P < .001) between spleen stiffness and the varix grade was found. The optimal spleen stiffness cutoff value for predicting varices was 3.16 m/s (AUROC = 0.83). CONCLUSIONS: Liver and spleen stiffness values measured by ARFI elastography are reliable predictors of liver fibrosis. Spleen stiffness measured by ARFI can be used as a non-invasive method for determining the presence and severity of esophageal varices; however, evidence to support a similar role for liver stiffness is lacking.

Targeted delivery of bone mesenchymal stem cells by ultrasound destruction of microbubbles promotes kidney recovery in acute kidney injury.

The aim of the present study was to explore whether ultrasound microbubble destruction augments site-targeted engraftment of bone marrow mesenchymal stem cells (BM-MSCs) to kidney tissue and promotes recovery of the kidney in acute kidney injury (AKI) in rats. AKI was induced by the subcutaneous injection of mercuric chloride (HgCl2). Forty Sprague-Dawley (SD) rats were randomly divided into the following groups after the establishment of rat models of AKI (n = 10): (1) Model group alone (control group); (2) 1.0 W/cm² ultrasound (US) + microbubble (MB) (US/MB group); (3) MSCs group; and (4) 1.0 W/cm² US+MB + MSCs group (US/MB + MSCs group). The number of 4',6-diamidino-2-phenylindole (DAPI) labelled MSCs was evaluated by fluorescence microscopy and real-time polymerase chain reaction (RT-PCR) and Western blotting and histological examination were performed 7 days after MSCs transplantation. It was observed via fluorescence microscopy that the number of DAPI-labelled MSCs in the kidney for the US/MB + MSCs group was significantly more than the MSCs group (p < 0.05). The results from RT-PCR revealed that the US/MB and US/MB + MSCs groups markedly increased the level of inter-cellular adhesion molecule 1 (ICAM-1) messenger ribonucleic acid (mRNA) compared with the control group and the MSCs group (p < 0.05). Western blot analysis showed that the expression of hepatocyte growth factor (HGF) and epidermal growth factor (EGF) in the US/MB + MSCs group were markedly increased compared with the all other groups (p < 0.01). The extent of tubular necrosis and dilation was significantly milder in the US/MB + MSCs group (acoustic exposure conditions: 5s at 1 MHz and 1.0 W/cm² with a 5s pause, totalling 60 s) than the all other groups (p < 0.05). Microbubble destruction by 1.0 W/cm² ultrasound can promote both the homing of BM-MSCs to kidney tissue and the recovery of the kidney in AKI in rats.

The stiffness of the liver and spleen on ARFI Imaging pre and post TIPS placement: a preliminary observation.

PURPOSE: To prospectively assess the stiffness of the liver and spleen with acoustic radiation force impulse (ARFI) imaging pre and post transjugular intrahepatic portosystemic shunt (TIPS) placement. MATERIAL AND METHODS: Between February, 2011 and September, 2011, we prospectively measured stiffness of the liver and spleen with mean shear wave velocity (MSV, m/s) on ARFI imaging in 10 healthy volunteers (mean age 32.2 ± 10.3 years, age range 23-53 years) and 10 patients (mean age, 38.6 ± 6.4 years, age range 30-48 years) who underwent TIPS placement for treatment of portal hypertension (PHTN). The portal vein pressure was measured while placing the TIPS. To assess the changes in the stiffness of the liver and spleen following TIPS placement, we measured MSV of the liver and spleen one day before TIPS insertion and 4-9 days after TIPS placement (mean interval 5.9 ± 2.0 days, interval range 5 to 10 days). RESULTS: There was significant difference in portal vein pressure pre (27.67 ± 5.86 mmHg) and post (18.00 ± 6.93 mmHg) TIPS insertion (P<.01). The MSV of the liver in healthy subjects, patients with PHTN pre TIPS and patients with PHTN post TIPS measured 1.16 ± 0.06 m/s, 2.48 ± 0.39 m/s, and 2.37 ± 0.28 m/s, respectively. The MSV of the spleen in healthy subjects, patients with PHTN pre TIPS and patients with PHTN post TIPS measured 2.22 ± 0.22 m/s, 3.65 ± 0.32 m/s, and 3.27 ± 0.30 m/s, respectively. There were significant differences in MSV of the liver and spleen between healthy subjects and patients with PHTN (all P<.001). There was no significant difference in MSV of the liver pre and post TIPS placement (P>.05). However, a statistically significant difference in MSV of the spleen pre and Post TIPS placement (P<.001) was demonstrated. In addition, we observed a significant difference in spleen index between healthy subjects and patients with PHTN (P<.001), as well as between pre and post TIPS placement (P<.01). CONCLUSION: The MSV of the spleen measured with ARFI correlates well with portal vein pressure. Hence, the spleen stiffness by means of MSV on ARFI imaging can be used as a quantitative marker in monitoring the portal vein pressure as the function of the TIPS.

Transfection efficiency of TDL compound in HUVEC enhanced by ultrasound-targeted microbubble destruction.

The aim of the present study was to explore the gene transfection efficiency of Tat peptide/plasmid DNA/ liposome (TDL) compound combined with ultrasound-targeted microbubble destruction (UTMD) in human umbilical vein endothelial cell (HUVEC). Tat peptide, plasmid DNA (pIRES2-EGFP-HGF) and Lipofectamine 2000 were used to prepare the TDL compound. Microbubbles were prepared using mechanic vibration. The expression of the report gene enhanced green fluorescent protein (EGFP) was observed using fluorescent microscopy and flow cytometry. The viability of HUVEC was measured by MTT assay. mRNA and protein of HGF was analyzed by reverse transcription-polymerase chain reaction and Western Blot. The intensity of green fluorescence and the gene transfection efficiency of TDL compound + microbubbles + ultrasound group were higher than those of other groups, and no significantly different viability was found between TDL compound + microbubbles + ultrasound group and the other groups. The HGF mRNA and HGF protein of TDL compound + microbubbles + ultrasound group were higher than those of other groups. Our finding demonstrated that UTMD could enhance the transfection efficiency of TDL compound without obvious effects on the cell viability of HUVEC, suggesting that the combination of UTMD and TDL compound might be a useful tool for the gene therapy of ischemic heart disease.

Relationship between myocardial ultrasonic integrated backscatter and mitochondria of the myocardium in dogs.

OBJECTIVE: This study aimed to explore the relationship between integrated backscatter (IBS) and mitochondria in arrested myocardium. METHODS: Twelve open-chest dogs were randomly divided into two groups: one group with cardiac arrest in systole and the other with cardiac arrest in diastole. IBS images at parasternal papillary muscle short-axis view were stored at different time frames (0, 30, and 60 min after cardiac arrest). The values of ultrasonic IBS were obtained using the acoustic densitometry technique. After ultrasound examination, tissue samples of corresponding times were harvested and observed under the transmission electron microscope. The microscopic images were analyzed using a computer imaging analysis system to obtain the stereological parameters of mitochondria. The correlation between IBS and the stereological parameters was analyzed. RESULTS: After cardiac arrest, swollen mitochondria with electron-lucent matrix could be observed in some myofibers following the progression of time. The alteration of IBS correlated well with that of mitochondrial stereological parameters, such as volume density (Vv), surface density (Sv), average volume (v), average surface area (s), and specific surface (Rsv, ratio between surface and volume). CONCLUSION: Mitochondria might be an important scatterer in the myocardium for IBS.

[Study on the inhibitive effect of Astragalus Injection solution on hepatic fibrosis in rats].

OBJECTIVE: To investigate the effect of Astragalus Injection solution on rat hepatic stellate cells (HSC) and hepatic fibrosis. METHODS: HSCs of rats were incubated with various concentrations of Astragalus Injection solution (0 mg/ml, 25 mg/ml, 50 mg/ml, 100 mg/ml, 200 mg/ml, 400 mg/ml) for 24, 48 and 72 hours. Cell proliferation was detected with 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphennyltetrazolium bromide (MTT) colorimetric assay. Cell cycle was detected with flow cytometry. Cell apoptosis was detected with acridine orange/ethidium bromide (AO/EB) fluorescent staining and flow cytometry. In vivo, rats were randomly allocated into a normal control group, a model control group and an Astragalus Injection group. Astragalus Injection (800 mg.kg-1.d-1) was administered to rats of the Astragalus Injection group. Rats of the model control group received saline. Serum concentrations of hyaluronic acid (HA) and laminin (LN), hepatic tissue activity of superoxide dismutase (SOD), and hepatic tissue contents of malondialdehyde (MDA) were measured in these groups at 8 weeks. Hepatic tissue expression of LN was assessed by using immunohistochemistry. The pathological changes of hepatic tissues were examined by hematoxylin-eosin (HE) and van Gieson (VG) staining of their histological slides. RESULTS: In vitro, compared with the 0 mg/ml group, the proliferation of HSCs in other concentration groups was significantly inhibited by Astragalus Injection solution in a dose and time dependent manner, the cell proliferation cycle of HSCs was blocked in the G2-M phase, there was no apoptosis of HSCs in AO/EB fluorescent staining and flow cytometry. In vivo, compared with rats of the model control group, the rats of the Astragalus Injection solution treated group had remarkably decreased serum HA and LN levels (114.3+/-25.6) microg/L vs (85.6+/-37.3) microg/L and (78.8+/-11.7) microg/L vs (66.8+/-17.6) microg/L, P < 0.05, and liver MDA level (3.7+/-0.4) micromol/g protein vs (2.4+/-0.2) micromol/g protein, P < 0.01, but had increased activity of liver SOD (49.6+/-5.7) NU/mg protein vs (75.9+/-5.9) NU/mg protein, P < 0.01. Microscopic studies revealed that the livers of rats receiving Astragalus Injection solution showed decreases in fibrosis and in expression of LN. CONCLUSIONS: Astragalus Injection solution has an inhibitive effect on experimental hepatic fibrogenesis. The mechanisms of its effects might possibly be associated with its antioxidant activity, expression of decreasing LN and its inhibition of HSCs proliferation.

[Effect and mechanism of Tanshensu on fibrotic rats].

OBJECTIVE: To investigate the effect and mechanism of Tanshensu on experimental fibrotic rats. METHODS: Pigs serum was used to induce liver fibrosis in Wistar rats. The rats in Tanshensu-treated group were injected peritoneally with Tanshensu solution at the dose of 300 mg x kg(-1) x d(-1), and the rats in model-control group and normal-control group received the same volume of double distill water. At the end of the twelfth week, the hepatic stellate cells (HSCs) were isolated from the liver of one rat in model-control group using in-situ perfusion with pronase and collagenase, then density gradient centrifugation, and the other rats were killed to take the serum and liver samples. MTT colorimetric assay was used for detecting the proliferation of HSCs and flow cytometry was used for observing the cell cycles of HSCs under different concentrations of Tanshensu. The hyaluronic acid (HA) level in serum was detected and the morphological changes of liver tissue were observed. RESULTS: There was a decline of serum HA level in Tanshensu-treated group compared to that of the model-control group (231.4 ng/ml +/- 41.1 ng/ml vs. 398.7 ng/ml +/- 54.5 ng/ml, F =154.796, P < 0.05). Both HE and VG stain showed a decline of liver fibrosis degree in Tanshensu-treated group. And Tanshensu had an inhibition effect on the proliferation of HSCs at the concentrations of 50 mg/L, 100 mg/L, and 200 mg/L (1.60x10(-2) +/- 8.17x10(-4), 1.10x10(-2) +/- 1.41x10(-3), and 6.75x10(-3) +/- 3.30x10(-3) vs. 7.18x10(-2) +/- 1.71x10(-3), F =1154.221, P <0.01). CONCLUSIONS: Tanshensu shows a therapeutic effect on liver fibrosis in rats induced by pig's serum through inhibiting the proliferation of hepatic stellate cells.