Delivery and Transcriptome Assessment of an In Vitro Three-Dimensional Proximal Tubule Model Established by Human Kidney 2 Cells in Clinical Gelatin Sponges.

The high prevalence of kidney diseases and the low identification rate of drug nephrotoxicity in preclinical studies reinforce the need for representative yet feasible renal models. Although in vitro cell-based models utilizing renal proximal tubules are widely used for kidney research, many proximal tubule cell (PTC) lines have been indicated to be less sensitive to nephrotoxins, mainly due to altered expression of transporters under a two-dimensional culture (2D) environment. Here, we selected HK-2 cells to establish a simplified three-dimensional (3D) model using gelatin sponges as scaffolds. In addition to cell viability and morphology, we conducted a comprehensive transcriptome comparison and correlation analysis of 2D and 3D cultured HK-2 cells to native human PTCs. Our 3D model displayed stable and long-term growth with a tubule-like morphology and demonstrated a more comparable gene expression profile to native human PTCs compared to the 2D model. Many missing or low expressions of major genes involved in PTC transport and metabolic processes were restored, which is crucial for successful nephrotoxicity prediction. Consequently, we established a cost-effective yet more representative model for in vivo PTC studies and presented a comprehensive transcriptome analysis for the systematic characterization of PTC lines.

Efficient energy transfer from Bi3+ to Mn2+ in CaZnOS for WLED application.

A series of Bi3+ and Mn2+ co-doped CaZnOS phosphors with a tunable emission color have been synthesized by a high temperature solid-state reaction method. Their crystal structure, spectroscopic properties, energy transfer and thermal quenching have been investigated systematically. An intense blue-green emission band at 485 nm and a red emission band at 616 nm were observed at an excitation wavelength of 375 nm, owing to the 3P1,0→1S0 transition of Bi3+ and the 4T1(4G) →6A1(6S) transition of Mn2+, respectively. The tunable color from blue-green, white light to red light can be obtained by varying the Mn2+ ion concentration from 0.005 to 0.015 in CaZnOS:Bi3+. The decay time decreased from 642 to 273 ns with the Mn2+ ion concentration x increasing from 0.005 to 0.015, and the energy transfer efficiency ηT can reach up to 65% in the CaZnOS:Bi3+,0.015Mn2+ phosphor. As the temperature increases from 300 to 420 K, the emission intensity is maintained at 67%, and the activation energy Ea is estimated to be 0.28 eV. An LED fabricated using CaZnOS:Bi3+,0.01Mn2+ exhibited the chromaticity coordinates and corrected color temperature (CCT) of (0.338, 0.364) and 4655 K, respectively. These results validate the promising applications of the CaZnOS:Bi3+,Mn2+ phosphor in UV white LEDs.

Rosmarinic Acid Attenuates Sodium Taurocholate-Induced Acute Pancreatitis in Rats by Inhibiting Nuclear Factor-κB Activation.

Rosmarinic Acid (RA), a caffeic acid ester, has been shown to exert anti-inflammation, anti-oxidant and antiallergic effects. Our study aimed to investigate the effect of RA in sodium taurocholate ( NaTC )-induced acute pancreatitis, both in vivo and in vitro. In vivo, RA (50 mg/kg) was administered intraperitoneally 2 h before sodium taurocholate injection. Rats were sacrificed 12 h, 24 h or 48 h after sodium taurocholate injection. Pretreatment with RA significantly ameliorated pancreas histopathological changes, decreased amylase and lipase activities in serum, lowered myeloperoxidase activity in the pancreas, reduced systematic and pancreatic interleukin-1 ß (IL-1ß), IL-6, and tumor necrosis factor-α (TNF-α) levels, and inhibited NF-κB translocation in pancreas. In vitro, pretreating the fresh rat pancreatic acinar cells with 80 µ mol/L RA 2 h before 3750 nmol/L sodium taurocholate or 10 ng/L TNF-α administration significantly attenuated the reduction of isolated pancreatic acinar cell viability and inhibited the nuclear activation and translocation of NF-κB. Based on our findings, RA appears to attenuate damage in sodium taurocholate-induced acute pancreatitis and reduce the release of inflammatory cytokines by inhibiting the activation of NF-κB. These findings might provide a basis for investigating the therapeutic role of RA in managing acute pancreatits.

Tetraspanin CD9 is involved in pancreatic damage during caerulein-induced acute pancreatitis in mice.

OBJECTIVE: Pancreatic acinar cell necrosis and subsequent inflammatory response aggravate acute pancreatitis (AP). Tetraspanin CD9 has been reported to mediate inflammatory signaling by regulating molecular organization at the cell surface. This study aimed to investigate the role of CD9 in caerulein-induced AP (CIP) in mice. METHODS: The expression of CD9 was detected in CIP in mice in vivo and cholecystokinin (CCK)/recombinant mouse tumor necrosis factor (rmTNF)-α induced pancreatic acinar cell death in vitro by quantitative real-time polymerase chain reaction, Western blot and immunofluorescence. The roles of CD9 in pancreatic acinar cell death and inflammatory response were further studied through the deletion of CD9 expression using small interfering RNA (siRNA). RESULTS: CD9 was markedly upregulated in pancreatic tissues in mice during the early onset of CIP and was located mainly at the pancreatic acinar cell surface, which was associated with pancreatic damage. Additionally, incubation with CCK or rmTNF-α directly increased the expression of CD9 in isolated mice pancreatic acinar cells in vitro. The deletion of CD9 expression partially reversed both pancreatic acinar cell death induced by CCK and mRNA levels of proinflammatory cytokines produced by damaged acinar cells. CONCLUSION: These results indicate that increased CD9 expression may be involved in pancreatic injury, possibly via the promotion of cytokine expressions in CIP in mice.

Catalpol ameliorates sodium taurocholate-induced acute pancreatitis in rats via inhibiting activation of nuclear factor kappa B.

Catalpol, an iridoid glucoside extracted from the traditional Chinese herbal medicine, Rehmannia glutinosa, is reported to exert neuroprotective, anti-inflammatory, anti-tumor and anti-apoptotic effects. The main aim of the present study was to investigate whether catalpol ameliorates experimental acute pancreatitis (AP) induced by sodium taurocholate (STC). AP was induced in rats via retrograde injection of 4% STC (0.1 mL/100 g) into the biliopancreatic duct. Rats were pre-treated with saline or catalpol (50 mg/kg) 2 h before STC injection. At 12, 24 and 48 h after injection, the severity of AP was evaluated using biochemical and morphological analyses. Pretreatment with catalpol led to a significant reduction in serum amylase and lipase activities, pancreatic histological damage, myeloperoxidase (MPO) activity, interleukin (IL)-1ß, IL-6 and TNF-α levels, and activation of nuclear factor kappa B (NF-κB). Moreover, administration of catalpol increased the viability of pancreatic acinar cells and inhibited NF-κB expression in vitro. Our results collectively support the potential of catalpol as a highly effective therapeutic agent for treatment of AP.

[Ultrasound tissue characterization of hepatic fat in rats using radiofrequency signal analysis].

OBJECTIVE: To investigate the significance of multi-parameter quantitative evaluation of hepatic fat using ultrasound radiofrequency signal analysis. METHODS: Thirty two SD rats were divided into two groups, with 24 having fatty livers and 8 serving as normal controls. Radiofrequency signals were sampled with a 13-MHz ultrasound probe and digitized at 40 MHz in 16-bit resolution. Four statistical parameters of the radiofrequency envelope [Mean, Mean/SD ratio (MSR), skewness (SK), and kurtosis (KU)] within the ROI were calculated offline, and their ability to diagnose fatty liver was analyzed. RESULTS: The rats with fatty livers had greater Mean and MSR but lower skewness and kurtosis than the controls. The areas under the ROC curve of Mean, MSR, skewness and kurtosis for diagnosing fatty livers were 0.85, 0.96, 0.98, and 0.98 respectively. The sensitivity and specificity of Mean, MSR, skewness and kurtosis for diagnosing fatty livers were 70.8%/88.9%, 87.5%/100%, 95.8%/100% and 95.8%/100% respectively, whereas conventional ultrasound achieved only 68.2% in sensitivity and 66.7% in specificity. CONCLUSION: Compared with conventional ultrasound, radiofrequency signal analysis is more accurate in diagnosing fatty livers.

Can contrast-enhanced ultrasound evaluate the severity of acute pancreatitis?

OBJECTIVES: To investigate the ability of contrast-enhanced ultrasound (CEUS) in the assessment of acute pancreatitis (AP), as well as its diagnostic accuracy in the evaluation of the severity of pancreatitis. METHODS: A prospective double-blind study was carried out in 33 AP patients from May 2007 to January 2008. Each patient underwent both CEUS and contrast-enhanced computed tomography (CECT) with the time interval between two examinations less than 72 h. Using CECT as gold standard, the ability of CEUS to diagnose pancreatic necrosis as well as peripancreatic effusion and/or complications, and its diagnostic value in the evaluation of the severity of pancreatitis, were investigated. Balthazar's grading system was used to measure CT and ultrasound severity indices (CTSI and USSI), and the correlation between CTSI and USSI was tested by Spearman's rank correlation coefficient. RESULTS: A strong correlation between CTSI and USSI was found (r = 0.92, P < 0.01).The sensitivity, specificity, accuracy, positive and negative predictive value of CEUS in the diagnosis of pancreatic parenchyma necrosis were 90, 95, 94, 90 and 95%, in the diagnosis of peripancreatic effusion and/or complications were 83, 100, 93, 100 and 91%, and in the diagnosis of severe pancreatitis were 97, 67, 94, 97 and 67%, respectively. CONCLUSIONS: CEUS has shown to be of clinical value in the assessment of pancreatic necrosis as well as peripancreatic complications in AP and has a high diagnostic accuracy in the evaluation of the severity of pancreatitis. Further studies are needed to add it to the diagnostic algorithm for acute pancreatitis.

Living donor liver transplantation using dual grafts: ultrasonographic evaluation.

AIM: To evaluate the dual-graft living donor liver transplantation (LDLT) with ultrasonography, with special emphasis on the postoperative complications. METHODS: From January 2002 to August 2007, 110 adult-to-adult LDLTs were performed in West China Hospital of Sichuan University. Among them, dual-graft implantations were performed in six patients. Sonographic findings of the patients were retrospectively reviewed. RESULTS: All the six recipients survived the dual-graft adult-to-adult LDLT surgery. All had pleural effusion. Four patients had episodes of postoperative abdominal complications, including fluid collection between the grafts in three patients, intrahepatic biliary dilatation in two, hepatofugal portal flow of the left lobe in two, and atrophy of the left lobe in one. CONCLUSION: Although dual-graft LDLT takes more efforts and is technically complicated, it is safely feasible. Postoperative sonographic monitoring of the recipient is important.

CEUS: a new imaging approach for postoperative vascular complications after right-lobe LDLT.

AIM: To investigate contrast-enhanced ultrasound (CEUS) for early diagnosis of postoperative vascular complications after right-lobe living donor liver transplantation (RLDLT). METHODS: The ultrasonography results of 172 patients who underwent RLDLT in West China Hospital, Sichuan University from January 2005 to June 2008 were analyzed retrospectively. Among these 172 patients, 16 patients' hepatic artery flow and two patients' portal vein flow was not observed by Doppler ultrasound, and 10 patients' bridging vein flow was not shown by Doppler ultrasound and there was a regional inhomogeneous echo in the liver parenchyma upon 2D ultrasound. Thus, CEUS examination was performed in these 28 patients. RESULTS: Among the 16 patients without hepatic artery flow at Doppler ultrasound, CEUS showed nine cases of slender hepatic artery, six of hepatic arterial thrombosis that was confirmed by digital subtraction angiography and/or surgery, and one of hepatic arterial occlusion with formation of lateral branches. Among the two patients without portal vein flow at Doppler ultrasound, CEUS showed one case of hematoma compression and one of portal vein thrombosis, and both were confirmed by surgery. Among the 10 patients without bridging vein flow and with liver parenchyma inhomogeneous echo, CEUS showed regionally poor perfusion in the inhomogeneous area, two of which were confirmed by enhanced computed tomography (CT), but no more additional information about bridging vein flow was provided by enhanced CT. CONCLUSION: CEUS may be a new approach for early diagnosis of postoperative vascular complications after RLDLT, and it can be performed at the bedside.

Sonographic evaluation of vessel grafts in living donor liver transplantation recipients of the right lobe.

AIM: To evaluate the vessel grafts (VG) used to reconstruct the middle hepatic vein (MHV) tributaries with ultrasonography. METHODS: Twenty-four patients undergone living donor liver transplantation were enrolled in our study. MHV tributaries larger than 5 mm in diameter were reconstructed with interposition VG. Blood flow of the graft and interposition VG was checked by Doppler ultrasonography daily in the first 2 postoperative weeks and monthly followed up after discharge. The sensitivity of VG detected by ultrasonography was assessed using surgical records as references. Student's t test was used to compare the velocity of VG and occluded VG in chronic patents (> 3 mo). RESULTS: Thirty-one VG were used to reconstruct the MHV tributaries. Ultrasonography identified 96.7% (30/31) of large MHV tributaries and 90.3% (28/31) of VG. The diameter of VG was 5.6 +/- 0.8 mm and the velocity of VG was 19.7 +/- 8.1 cm/s. Two VG (2/31, 6.5%) were occluded on the first postoperative day in one patient who suffered from persistent ascites and had a prolonged recovery of liver function. Twenty-six VG (26/31, 83.9%) were patent 2 wk after operation. Six (6/31, 19.4%) VG were patent over 3 mo after operation. Intrahepatic venous collaterals were detected in 29.2% (7/24) patients. The velocity of VG and occluded VG was 30.1 +/- 5.6 cm/s, 16.5 +/- 5.8 cm/s, respectively, in chronic patents. The difference between two groups was statistically significant (P < 0.001). CONCLUSION: Our results indicate that most VG are patent in the first postoperative week while only a small portion with a higher velocity remains patent after 3 mo. Intrahepatic venous collaterals can be observed in some patients after occlusion of VG.

Value of contrast-enhanced intraoperative ultrasound for cirrhotic patients with hepatocellular carcinoma: a report of 20 cases.

AIM: To assess the clinical value of contrast-enhanced intraoperative ultrasound (CE-IOUS) as a novel tool in partial hepatectomy for cirrhotic patients with hepatocellular carcinoma (HCC). METHODS: From January 2007 to September 2007, a total of 20 consecutive cirrhotic patients with HCC scheduled to undergo partial hepatectomy were studied. Preoperative contrast enhanced computer tomography (CT) and/or magnetic resonance (MR) scans were performed within 1-2 wk before operation. Intraoperative ultrasound (IOUS) and CE-IOUS were carried out after mobilization of the liver. Lesions on precontrast and postcontrast scans were counted and mapped. CE-IOUS was performed with intravenous injection of ultrasound contrast agents SonoVue (Bracco Imaging, Milan, Italy). Arterial, portal and late phases of contrast enhancement were recorded and analyzed. Nodules showing arterial phase hyper-enhancing and/or hypo-enhancing in late parenchymal phase were considered malignant and removed surgically. Ultrasound-guided biopsy and ethanol ablation would be an option if the nodule could not be removed surgically. Newly detected nodules on IOUS showing iso-enhancement in both arterial and late phases were considered benign. These nodules were either removed surgically if they were close to the main lesion or followed by examinations of alpha-fetoprotein (AFP) level and ultrasound and/or CT/MR every 3 mo. RESULTS: IOUS found 41 nodules in total, among which 17 (41.46%) were newly detected compared to preoperative imaging. Thirty-three nodules were diagnosed malignant by CE-IOUS, including one missed by IOUS. The sensitivity and specificity of CE-IOUS on detecting HCC nodules are 100% (33/33 and 100% (9/9), respectively. Nine nodules were considered benign by CE-IOUS, four was confirmed at histology and five by follow-up. CE-IOUS changed the surgical strategy in 35% (7/20) of patients and avoid unnecessary intervention in 30% (6/20) of patients. CONCLUSION: CE-IOUS is a useful means to characterize the nodules detected by IOUS in cirrhotic liver, to find isoechoic HCC nodules which can not be shown on IOUS and to improve the accuracy of conventional IOUS, thus it can be used as an essential tool in the surgical treatment of cirrhotic patients with HCC.

Cutting edge: dendritic cells are essential for in vivo IL-12 production and development of resistance against Toxoplasma gondii infection in mice.

A powerful IFN-gamma response is triggered upon infection with the protozoan parasite, Toxoplasma gondii. Several cell populations, including dendritic cells (DCs), macrophages, and neutrophils, produce IL-12, a key cytokine for IFN-gamma induction. However, it is still unclear which of the above cell populations is its main source. Diphtheria toxin (DT) injection causes transient DC depletion in a transgenic mouse expressing Simian DT receptors under the control of the CD11c promoter, allowing us to investigate the role of DCs in IL-12 production. T. gondii-inoculated DT-treated and control groups were monitored for IL-12 levels and survival. We show in this study that DC depletion abolished IL-12 production and led to mortality. Furthermore, replenishment with wild-type, but not MyD88- or IL-12p35-deficient, DCs rescued IL-12 production, IFN-gamma-induction, and resistance to infection in DC-depleted mice. Taken together, the results presented in this study indicate that DCs constitute the major IL-12-producing cell population in vivo during T. gondii infection.