Circulating exosomal miR-155-5p contributes to severe acute pancreatitis-associated intestinal barrier injury by targeting SOCS1 to activate NLRP3 inflammasome-mediated pyroptosis.

Severe acute pancreatitis (SAP) represents a common and serious disease that can cause intestinal barrier dysfunction. However, the pathogenesis of this barrier dysfunction remains unclear. Exosomes are a new intercellular communication method involved in multiple diseases. Consequently, the present study sought to determine the function of circulating exosomes in barrier dysfunction associated with SAP. A rat model of SAP was established by injecting biliopancreatic duct with 5% sodium taurocholate. Circulating exosomes were purified from SAP (SAP-Exo) and sham operation rats (SO-Exo) using a commercial kit. In vitro, SO-Exo and SAP-Exo were cocultured with rat intestinal epithelial (IEC-6) cells. In vivo, naive rats were treated with SO-Exo and SAP-Exo. We found SAP-Exo-induced pyroptotic cell death and barrier dysfunction in vitro. In addition, miR-155-5p exhibited a remarkable increase in SAP-Exo than SO-Exo, and miR-155-5p inhibitor partially abolished the negative effect of SAP-Exo on IEC-6 cells. Furthermore, miRNA functional experiments revealed that miR-155-5p could induce pyroptosis and barrier loss in IEC-6 cells. Overexpression of suppressor of cytokine signaling 1 (SOCS1), a miR-155-5p target, could partially reverse IEC-6 cells from the harmful impact of miR-155-5p. In vivo, SAP-Exo significantly triggered pyroptosis in intestinal epithelial cells and caused intestinal injury. In addition, blocking exosome release with GW4869 attenuated intestinal injury in SAP rats. In summary, our study demonstrated that miR-155-5p is highly enriched in circulating exosomes from SAP rat plasma and can be transported to intestinal epithelial cells, where it targets SOCS1 to activate NOD-like receptor protein 3 (NLRP3) inflammasome-mediated pyroptosis leading to intestinal barrier damage.

Elevation of HO-1 expression protects the intestinal mucosal barrier in severe acute pancreatitis via inhibition of the MLCK/p-MLC signaling pathway.

In severe acute pancreatitis (SAP), intestinal mucosal barrier damage can cause intestinal bacterial translocation and induce or aggravate systemic infections. Heme oxygenase-1 (HO-1) is a validated antioxidant and cytoprotective agent. This research aimed to investigate the effect and mechanism of HO-1 on SAP-induced intestinal barrier damage in SAP rats. Healthy adult male Sprague-Dawley rats were randomly separated into the sham-operated group, SAP group, SAP + Hemin group, and SAP + Znpp group. The rat model of SAP was established by retrograde injection of sodium taurocholate (5%) into the biliopancreatic duct. Hemin (a potent HO-1 activator) and Znpp (a competitive inhibitor of HO-1) were injected intraperitoneally in the selected groups 24 h before SAP. Serum and intestinal tissue samples were collected for analysis after 24 h in each group. Hemin pretreatment significantly reduced systemic inflammation, intestinal oxidative stress, and intestinal epithelial apoptosis in SAP by increasing HO-1 expression. Meanwhile, pretreatment with Hemin abolished the inhibitory effect on the expression of the tight junction proteins and significantly inhibited the activation of the MLCK/P-MLC signaling pathway. Conversely, ZnPP completely reversed these effects. Our study indicates that upregulation of HO-1 expression attenuates the intestinal mucosal barrier damage in SAP. The protective effect of HO-1 on the intestine is attributed to MLCK/p-MLC signaling pathway inhibition.

Effect of STING signaling on intestinal barrier damage in severe acute pancreatitis.

BACKGROUND: Patients with severe acute pancreatitis (SAP) have a compromised intestinal barrier with decreased barrier function and increased cell death. Intestinal epithelial cells (IECs) create a physicochemical barrier that anchors bacteria in the intestine. Recent studies have shown that the stimulator of interferons genes (STING) signaling pathway plays an important function in a number of inflammatory conditions. METHODS: The rat SAP model was established by retrograde injection of freshly prepared sodium taurocholate into the biliopancreatic duct. Serum amylase (AMY), lipase (LIPA), interleukin (IL)-6, interferon (IFN)-ß, tumor necrosis factor (TNF)-α, intestinal-type fatty acid binding protein (FABP2), diamine oxidase (DAO) and endotoxin (ET) levels were measured in rats. H&E staining was used to assess histological changes in the intestine and pancreas. The expression of intestinal epithelial cell tight junction (TJ) proteins and STING signaling pathway proteins and genes were measured by RT- PCR, Western blot and immunofluorescence staining were used to analyze. The expression of STING signaling pathway proteins in pancreas were measured by Western blot were used to analyze. TUNEL was used to detect IECs death. RESULTS: Upregulation of STING pathway-related proteins and genes occurred after sap-induced IECs. In addition, C-176 reduced serum AMY, LIPA, TNF-α, IL-6, INF-ß, FABP2, DAO and endotoxin levels and decreased pancreatic and intestinal histopathological injury in SAP rats; DMXAA aggravated serum AMY, LIPA, TNF-α, IL-6, INF-ß, FABP2, DAO and endotoxin levels and increased pancreatic and intestinal histopathological injury in SAP rats. CONLUSIONS: The results suggest that inhibition of STING signaling can alleviate IECs after SAP, and activation of STING signaling can aggravate IECs after SAP.

Inhibition of Ferroptosis Attenuates Acute Kidney Injury in Rats with Severe Acute Pancreatitis.

BACKGROUND: Acute kidney injury (AKI) is a frequent complication of severe acute pancreatitis (SAP). Ferroptosis is involved in a range of diseases. However, the role of ferroptosis in SAP-induced AKI has yet to be elucidated. AIMS: We aimed to investigate whether ferroptosis is induced in the kidney after SAP and whether inhibition of ferroptosis ameliorates AKI in a rat model of SAP. METHODS: Sodium taurocholate (5%) was retrogradely perfused into the biliopancreatic duct to establish a model of SAP with AKI in rats. The levels of serum amylase, lipase, tumor necrosis factor (TNF)-α, interleukin (IL)-6, creatinine (Cr) and blood urea nitrogen (BUN) in rats were measured. We also determined the biochemical and morphological changes associated with ferroptosis in renal tissue, including iron accumulation, lipid peroxidation assays, and mitochondrial shrinkage. H&E staining was used to assess pancreatic and renal histological changes. Western blot analysis, RT-PCR, and immunofluorescence staining were performed to analyze the expression of ferroptosis-related proteins and genes. RESULTS: SAP-induced AKI was followed by iron accumulation, increased lipid peroxidation, and upregulation of ferroptosis-related proteins and genes. Twenty-four hours after SAP, TEM confirmed the presence of typical shrunken mitochondria. Furthermore, treatment with liproxstatin-1 lowered the levels of serum amylase, TNF-α, IL-6, Cr and BUN, decreased kidney lipid peroxidation and alleviated pancreatic and renal histopathology injury in SAP rats. CONCLUSION: Our findings are the first to demonstrate the involvement of ferroptosis in SAP-associated renal damage and present ferroptosis as a therapeutic target for effective treatment of SAP-induced AKI.

Assessment of an advanced virtual monoenergetic reconstruction technique in cerebral and cervical angiography with third-generation dual-source CT: Feasibility of using low-concentration contrast medium.

OBJECTIVES: To investigate the feasibility of low-concentration contrast media (LC-CM) in cerebral and cervical dual-energy CT angiography (DE-CTA) using an advanced monoenergetic (Mono+) reconstruction technique. METHODS: Sixty-five consecutive patients prospectively selected to undergo cerebral and cervical DE-CTA were randomised into two groups: 32 patients (63.7 ± 9.7 years) in the high-concentration contrast medium (HC-CM) group with iopromide 370 and 33 patients (60.7 ± 10.8 years) in the low-concentration contrast medium (LC-CM) group with iodixanol 270. Traditional monoenergetic (Mono) and Mono+ images from 40 to 100 keV levels (at 10-keV intervals) and the standard mixed (Mixed, 120 kVp equivalent) images were reconstructed. Subjective image quality parameters included the contrast-to-noise ratio (CNR) and objective image quality parameters were evaluated and compared between the two groups. RESULTS: The 40-keV Mono+ images in the LC-CM group showed comparable objective CNR (common carotid arteries: 83.7 ± 24.5 vs. 78.1 ± 23.2; internal carotid arteries: 82.2 ± 26.8 vs. 76.8 ± 24.1; middle cerebral arteries: 72.5 ± 24.6 vs. 70.6 ± 19.2; all p > 0.05) and subjective image scores (3.95 ± 0.19 vs. 3.83 ± 0.35; p > 0.05) compared with Mixed images in the HC-CM group. CONCLUSION: The Mono+ reconstruction technique could reduce the concentration of iodinated CM in the diagnosis of cerebral and cervical angiography. KEY POINTS: • Mono+ shows decreased noise and superior CNR compared with Mono. • The 40-keV Mono+ images show the highest CNR in the LC-CM group. • The Mono+ reconstruction technique could reduce the concentration of iodinated CM.

Autophagy Strengthens Intestinal Mucosal Barrier by Attenuating Oxidative Stress in Severe Acute Pancreatitis.

BACKGROUND: Intestinal mucosal barrier dysfunction can be caused by severe acute pancreatitis (SAP). It is normally associated with changes to mucosal autophagy and oxidative stress. OBJECTIVE: The aim of this study was to investigate the correlation between autophagy and oxidative stress on the intestinal mucosal barrier of SAP rat model. METHODS: SAP was induced by retrograde injection of sodium taurocholate (5%) into the biliopancreatic duct. Bacterial translocation (BT) was detected by 16S rDNA sequencing analysis. Morphological alterations in the pancreas and gut were determined by hematoxylin-eosin staining. Oxidative stress status was determined by measuring the level of intestinal malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx). Western blot, RT-PCR, and immunofluorescent staining were preformed to analyze the expression of tight junction and autophagy proteins. RESULTS: According to the sequencing analysis, rats in SAP group were divided into BT (+) group (n = 9) and BT (-) group (n = 8). Pancreatic and intestinal injuries in SAP group were significantly higher than sham operation group. The content of MDA was clearly elevated, and SOD as well as GPx activities were decreased in BT (+) group as compared with BT (-) group. The expression of LC3II and Beclin1 in BT (-) group was higher than that observed in BT (+). In contrast, BT (+) group had a higher level of claudin-2 and a lower level of zonula occluden-1, occludin, and claudin-1. CONCLUSION: These results suggest that activated autophagy may attenuate intestinal mucosal barrier dysfunction by preventing and reducing the oxidative stress in SAP.

Bacterial translocation contributes to cachexia and its possible pathway in patients with colon cancer.

GOALS AND BACKGROUND: There is increasing evidence that bacterial translocation (BT) might contribute to the occurrence and development of cancer cachexia, but the detailed mechanism remains unknown. Thus, we undertook further investigations into the association of BT with cancer cachexia and the possible pathway. STUDY: The colon cancer patients enrolled in this study were divided into cachectic and noncachectic. BT was analyzed by polymerase chain reaction and bacterial culture. Intestinal epithelial T-cell subsets and NK cells were evaluated using flow cytometry. Western blotting and immunofluorescence were used to check tight junction (TJ) proteins in intestinal epithelium. Fluorescence in situ hybridization and immunohistochemistry were used to detect the translocated bacteria and endotoxin. RESULTS: Compared with noncachectic patients, cachectic patients had a significantly higher BT ratio (P<0.001). We observed the translocated bacteria in the intestinal mucus layer associated with lower levels of T-cell subsets and NK cells in the intestinal epithelium in BT-positive patients (P<0.05). Endotoxin was detected within the small intestinal wall and the concentration of endotoxin decreased from the mucosal side to serosal side gradually in these patients. These were associated with an altered composition of TJs. CONCLUSIONS: This study suggests that BT may contribute to colon cancer in cachectic patients, and TJ could be the gateway to the possible pathway of BT.

Inhibition of circulating exosomes release with GW4869 mitigates severe acute pancreatitis-stimulated intestinal barrier damage through suppressing NLRP3 inflammasome-mediated pyroptosis.

Intestinal barrier dysfunction frequently occurs as a complication in cases of severe acute pancreatitis (SAP); however, no effective therapeutic methods are available because the precise mechanism remains obscure. Recent research has elucidated the role of circulating exosomes in the progression of SAP. Therefore, the present study explored whether inhibiting circulating exosomes release would improve intestinal barrier injury triggered via SAP and investigated the possible underlying mechanism. In vivo, we found that circulating exosomes release exhibited a considerable increase in SAP rats than in SO rats, and GW4869, a suppressor of exosomes release, significantly decreased exosomes release in SAP rats. We also observed that GW4869 suppressed NLRP3 inflammasome-mediated pyroptosis within the intestine and alleviated intestinal barrier injury within SAP. Moreover, the inflammatory response and remote organ (kidney and lung) injury associated with SAP improved after GW4869 treatment. In vitro, we confirmed that depletion of exosomes with GW4869 could partially abolish the destructive effects of SAP rat plasma on the viability and barrier function of IEC-6 cells. In summary, our findings show that the suppression of the release of circulating exosomes effectively inhibits the process of pyroptosis mediated by the NOD-like receptor protein 3 (NLRP3) inflammasome and, therefore, mitigates intestinal barrier dysfunction in SAP, suggesting that circulating exosomes may be a potential target for treating SAP.

A retrospective study of non-equidistant interstitial brain CT perfusion scanning and prediction of time to peak.

Background: Eexploring the limits of CT cranial perfusion scan acquisition intervals and predicting time to peak. Methods: A retrospective analysis was conducted on 45 patients with suspected stroke who underwent brain CTP scans. Different sampling intervals were set based on the TDC. The patients were divided into four groups: Group 1 underwent continuous scanning with a uniform interval of 1.5 s; Group 2 had a uniform interval of 3 s; Group 3 had a 1.5-s interval between arterial and venous peak vertices with 1 point retained before and after the peak for 1.5 s and with a remaining acquisition interval of 4.5 s; and Group 4 had a uniform interval of 4.5 s. Statistical analysis was performed on the perfusion parameters of each group. Additionally, in 286 patients who underwent head and neck CTA examinations, the peak time of contrast medium was recorded, and the peak time was predicted based on factors such as age, height, weight, heart rate, systolic blood pressure, diastolic blood pressure, triglycerides, and total cholesterol. The results compared with Group 1 and Group 2, as well as Group 1 and Group 3, the P values of CBF, CBV, MTT, and Tmax in the left and right cerebral hemispheres of healthy subjects and in the infarct and noninfarct areas of patients were all >0.05. A comparison between Group 1 and Group 4 showed that right cerebral hemisphere CBF and CBV, left cerebral hemisphere CBF, CBV, and Tmax, infarct area CBV and Tmax, and noninfarct area CBF, CBV, and MTT had P values > 0.05, while other groups all had P values < 0.05. Bland‒Altman analysis showed that the perfusion parameters in Group 1 were consistent with those in Group 2, and those in Group 1 were consistent with those in Group 3. The radiation doses in the second and third groups were lower, and the dose in the third group was lower than that in the second group. Conclusion: Continuous acquisition between the peak points of the arterial and venous phases, with 1 point reserved before and after the peak and a 4.5-s interval for the rest, represents the maximum time interval for CTP scanning and can effectively reduce the radiation dose. The formula Tmax (s) = 0.290 × height (cm) - 0.226 × heart rate (times/min) + 0.216 × age (years) - 1.901 × triglycerides (mmol/L) - 0.061 × systolic blood pressure (mmHg) - 7.216 (R2 = 0.449, F = 17.905, P < 0.01) was established for predicting time to peak enhancement.

Metallic artifacts-free spectral computed tomography angiography based on renal clearable bismuth chelate.

Computed tomography angiography (CTA) is one of the most important diagnosis techniques for various vascular diseases in clinic. However, metallic artifacts caused by metal implants and calcified plaques in more and more patients severely hinder its wide applications. Herein, we propose an improved metallic artifacts-free spectral CTA technique based on renal clearable bismuth chelate (Bi-DTPA dimeglumine) for the first time. Bi-DTPA dimeglumine owns the merits of ultra-simple synthetic process, approximately 100% of yield, large-scale production capability, good biocompatibility, and favorable renal clearable ability. More importantly, Bi-DTPA dimeglumine shows superior contrast-enhanced effect in CTA compared with clinical iohexol at a wide range of X-ray energies especially in higher X-ray energy. In rabbits' model with metallic transplants, Bi-DTPA dimeglumine assisted-spectral CTA can not only effectively mitigate metallic artifacts by reducing beam hardening effect under high X-ray energy, but also enables accurate delineation of vascular structure. Our proposed strategy opens a revolutionary way to solve the bottleneck problem of metallic artifacts in CTA examinations.

Inhibition of Caspase-11-Mediated Pyroptosis Alleviates Acute Kidney Injury Associated with Severe Acute Pancreatitis in Rats.

Background: Acute kidney injury (AKI) is a common complication in patients with severe acute pancreatitis (SAP). Caspase-11-mediated pyroptosis is essential for the progression of multiple diseases, but its role in SAP-induced AKI remains unknown.Aims: This research investigated whether caspase-11-mediated pyroptosis is involved in SAP-induced AKI and whether inhibiting caspase-11-mediated pyroptosis improves SAP-induced AKI.Methods: A rat model of SAP with AKI was established by slowly injecting 5% sodium taurocholate into the biliopancreatic duct, then wedelolactone (25 or 50 mg/kg), an inhibitor of caspase-11, was injected through the intra-peritoneum 1 and 6 h after SAP induction. Serum biochemical indexes, including serum amylase, lipase, interleukin (IL)-6, blood urea nitrogen (BUN), tumor necrosis factor (TNF)-α, and creatinine (Cr) in rats, were evaluated using biochemical test kits. Caspase-11 and gasdermin D (GSDMD) expression in the kidney tissues was evaluated by western blotting and immunohistochemical staining. IL-1ß and IL-18 levels in kidney tissues were detected by ELISA kits. Furthermore, histopathological alterations of pancreas and kidney were assessed by H&E staining.Results: The serum biochemical indexes and pyroptosis-related proteins in kidney tissues were significantly increased after SAP induction. Furthermore, wedelolactone decreased the expression of pyroptosis-linked proteins in kidney tissues, reduced serum lipase, amylase, IL-6, TNF-α, BUN, and Cr, and ameliorated the renal and pancreatic histological damage in SAP rats.Conclusion: Caspase-11-mediated pyroptosis contributes to SAP-induced AKI, and targeting caspase-11-mediated pyroptosis might be a novel treatment strategy for SAP-induced AKI.

Inhibition of angiotensin II type 1 receptor reduces oxidative stress damage to the intestinal barrier in severe acute pancreatitis.

Intestinal barrier injury is a common complication of severe acute pancreatitis (SAP), which is often accompanied by intestinal mucosal barrier injury and results in serious consequences. However, the exact mechanism remains unclear. We aimed to investigate whether angiotensin II type 1 receptor (AT1)-mediated oxidative stress is involved in SAP intestinal barrier injury and assessed the effects of inhibiting this pathway. The SAP model was established by retrograde bile duct injection of sodium taurocholate (5%). The rats were divided into three groups: the control group (SO), the SAP group (SAP), and the azilsartan intervention group (SAP + AZL). Serum amylase, lipase, and other indexes were measured to evaluate SAP severity in each group. Histopathological changes in the pancreas and intestine were evaluated by HE staining. The oxidative stress of intestinal epithelial cells was detected by superoxide dismutase and glutathione. We also detected the expression and distribution of intestinal barrier-related proteins. The results showed that the serum indexes, the severity of tissue damage, and the level of oxidative stress in the SAP + AZL group were significantly lower than in the SAP group. Our study provided hitherto undocumented evidence of AT1 expression in the intestinal mucosa, confirming that AT1-mediated oxidative stress is involved in SAP intestinal mucosal injury, and inhibiting this pathway could effectively reduce intestinal mucosal oxidative stress injury, providing a new and effective target for the treatment of SAP intestinal barrier injury.

Effects of Lipid Peroxidation-Mediated Ferroptosis on Severe Acute Pancreatitis-Induced Intestinal Barrier Injury and Bacterial Translocation.

Ferroptosis is a recently recognized type of regulated cell death characterized by iron- and lipid peroxidation-mediated nonapoptotic cell death. However, whether ferroptosis is involved in severe acute pancreatitis- (SAP-) induced intestinal barrier injury is unknown. The aim of this study was to investigate whether ferroptosis is involved in SAP-induced intestinal barrier injury, particularly intestinal epithelial cell (IEC) death, and determine whether the inhibition of ferroptosis would ameliorate intestinal barrier injury and prevent bacterial translocation (BT). Sodium taurocholate (5%) was retrogradely perfused into the biliopancreatic duct to establish a rat model of SAP. The rats were divided into three groups: sham operation (SO), SAP-induced intestinal barrier injury (SAP), and ferroptosis inhibitor liproxstatin-1 (SAP + Lip). Serum indexes were measured in the rats. In addition, the biochemical and morphological changes associated with ferroptosis were observed, including iron accumulation in intestinal tissue, lipid peroxidation levels, and mitochondrial shrinkage. Hematoxylin staining and eosin staining were used to assess histological tissue changes. Western blot, RT-PCR, and immunofluorescent staining were performed to analyze the expression of ferroptosis-related proteins and genes as well as tight junction. BT was detected by 16S rDNA sequencing analysis. The results indicated that ferroptosis was significantly induced in the IECs from rats with SAP and ferroptosis was mediated by lipid peroxidation. The specific lipid peroxidation of IECs clearly upregulated ferroptosis and exacerbated intestinal barrier injury. Furthermore, treatment with liproxstatin-1 lowered the levels of serum damage markers, decreased lipid peroxidation, and alleviated intestinal and acute remote organ injury in SAP rats. In addition, inhibition of ferroptosis reduced BT. Our findings are the first to demonstrate that ferroptosis contributes to SAP-induced intestinal barrier injury via lipid peroxidation-mediated IEC death. These results suggest that ferroptosis is a potential therapeutic target for SAP-induced intestinal barrier injury.

Effects of Bacterial Translocation and Autophagy on Acute Lung Injury Induced by Severe Acute Pancreatitis.

AIM: To reveal the role of bacterial translocation (BT) and autophagy in severe acute pancreatitis-induced acute lung injury (SAP-ALI). METHODS: Rats were separated into a control (sham-operation) group (n = 10) and a SAP group (n = 10) and a SAP group (. RESULTS: Levels of TNF-α, IL-6, lipase, and amylase in the SAP group were significantly higher than those in the control group (P < 0.01). Histopathological score and W/D ratio of the lung in the SAP-BT(+) group were significantly higher than that in the SAP-BT(-) group (P < 0.01). Histopathological score and W/D ratio of the lung in the SAP-BT(+) group were significantly higher than that in the SAP-BT(-) group (P < 0.01). Histopathological score and W/D ratio of the lung in the SAP-BT(+) group were significantly higher than that in the SAP-BT(-) group (P < 0.01). Histopathological score and W/D ratio of the lung in the SAP-BT(+) group were significantly higher than that in the SAP-BT(-) group (P < 0.01). Histopathological score and W/D ratio of the lung in the SAP-BT(+) group were significantly higher than that in the SAP-BT(-) group (P < 0.01). Histopathological score and W/D ratio of the lung in the SAP-BT(+) group were significantly higher than that in the SAP-BT(-) group (. CONCLUSIONS: BT can aggravate SAP-ALI with the increasing oxidative stress level, which may be related to the decrease of autophagy level.

Carbachol protects the intestinal barrier in severe acute pancreatitis by regulating Cdc42/F-actin cytoskeleton.

The present study aimed to investigate the effect of carbachol on the intestinal tight-junction barrier in a rat model of severe acute pancreatitis (SAP) without aggravating pancreatic injury, and to determine whether cell division cycle 42 (Cdc42)/F-actin could have a regulatory role. Rats were separated into a sham-operation (SO) group (n=10), SO + carbachol group (n=10), SAP group (n=60) and SAP + carbachol group (n=60). Sodium taurocholate (5%) was retrogradely injected into the biliopancreatic duct of rats to induce SAP. Subsequently, 16S rRNA sequencing was used to detect bacterial translocation (BT) in the gut of surviving animals. Hematoxylin and eosin staining was used to detect morphological changes in the pancreas and intestine. The expression of F-actin and tight junction proteins was analyzed by western blotting and immunofluorescence, and Cdc42 expression was analyzed by immunohistochemistry and western blotting. The results demonstrated that the intestinal injury in SO and SO + carbachol groups was lower than that in the SAP + carbachol group (P<0.05); however, the intestinal injury was similar in the SO and SO + carbachol groups (P>0.05), and was significantly more severe in the SAP group compared with the SAP + carbachol group (P<0.05). Similarly, pancreatic injury in the SAP and SAP + carbachol groups was significantly higher compared with the SO and SO + carbachol groups (P<0.05); however, pancreatic injury was similar in the SAP and SAP + carbachol groups (P>0.05), and in the SO and SO + carbachol groups (P>0.05). Furthermore, the mortality rate and BT in the SAP group were significantly higher compared with the SAP + carbachol group (mortality rate, 50% vs. 30%, P<0.05; BT, 60% vs. 33.3%, P<0.05). In addition, the expression of Cdc42, F-actin and claudin-2 was significantly higher in the SAP and SAP + carbachol groups compared with the SO and SO + carbachol groups (P<0.05), and the expression of occludin and zonula occludens-1 were significantly higher in the SO and SO + carbachol groups compared with the SAP and SAP + carbachol groups (P<0.05). In conclusion, these findings demonstrated that carbachol may protect the intestinal barrier in the SAP rat model without aggravating pancreatic injury via regulation of Cdc42/F-actin expression.

A computational study of energy barriers of structural transformations and hydrogen transfer in boehmite.

The crystal structure of boehmite (γ-AlOOH) contains a large amount of hydrogen bonds that are joined into chains by sharing hydrogen-bond donor and acceptor oxygen atoms. The hydrogen ions in the hydrogen-bond chains are highly mobile and have complicated structural characterizations, and this feature may well be utilized for proton-conducting applications, but the mechanism is unknown without the dynamic parameters of the hydrogen-transfer processes. We propose probable hydrogen-transfer paths and compute their energy barriers using density functional theory with van der Waals density functionals, on both perfect and vacancy-containing crystal structures. It is revealed that the energy barriers are generally below 21 kJ mol-1 in a perfect crystal, and 14 kJ mol-1 in a vacancy-containing structure. The low energy barriers are indicators of the high proton conductivity of boehmite even at room temperature.

Overexpression of UQCRC2 is correlated with tumor progression and poor prognosis in colorectal cancer.

Ubiquinol-cytochrome c reductase complex core protein 2 (UQCRC2) is an important subunit of mitochondrial respiratory complex III. However, its role in tumorigenesis and tumor progression remains unknown, especially with regards to colorectal cancer (CRC). In this research, we measured the expression of UQCRC2 protein by immunohistochemistry assay in 89 paired paraffin-embedded tumor tissues and corresponding adjacent normal tissues from patients with colorectal adenocarcinoma and investigated possible correlations of UQCRC2 expression with clinicopathological parameters and prognosis. We found that UQCRC2 was significantly upregulated in CRC tissues compared with adjacent normal tissues, and immunohistochemical UQCRC2 status was correlated to the depth of invasion (T), lymph node metastasis (N), advanced TNM stage. Multivariate analysis indicated that UQCRC2 remained an independent prognostic factor for poorer overall survival. Furthermore, we determined the role of UQCRC2-knockdown in CRC cells (RKO and HCT116) using lentivirus-mediated small hairpin RNAs (shRNAs). The effects of UQCRC2 knockdown on CRC cells (RKO and HCT116) proliferation were analyzed by cell proliferation and colony formation assay, and cell cycle and apoptosis were assessed by flow cytometry. We found that silencing UQCRC2 suppressed cell proliferation and colony formation in RKO and HCT116 cells, led to a cell cycle arrest and induced cell apoptosis in vitro. These results provided novel insights into the potential role of UQCRC2 in the tumorigenesis and progression of CRC, and revealed that UQCRC2 may serve as a new prognostic and therapeutic target in CRC.

[Effect of Scanning and Reconstruction Parameters on Three Dimensional Volume and CT Value Measurement of Pulmonary Nodules: A Phantom Study].

BACKGROUND: The computed tomography (CT) follow-up of indeterminate pulmonary nodules aiming to evaluate the change of the volume and CT value is the common strategy in clinic. The CT dose needs to considered on serious CT scans in addition to the measurement accuracy. The purpose of this study is to quantify the precision of pulmonary nodule volumetric measurement and CT value measurement with various tube currents and reconstruction algorithms in a phantom study with dual-energy CT. METHODS: A chest phantom containing 9 artificial spherical solid nodules with known diameter (D=2.5 mm, 5 mm, 10 mm) and density (-100 HU, 60 HU and 100 HU) was scanned using a 64-row detector CT canner at 120 Kilovolt & various currents (10 mA, 20 mA, 50 mA, 80 mA,100 mA, 150 mA and 350 mA). Raw data were reconstructed with filtered back projection and three levels of adaptive statistical iterative reconstruction algorithm (FBP, ASIR; 30%, 50% and 80%). Automatic volumetric measurements were performed using commercially available software. The relative volume error (RVE) and the absolute attenuation error (AAE) between the software measures and the reference-standard were calculated. Analyses of the variance were performed to evaluate the effect of reconstruction methods, different scan parameters, nodule size and attenuation on the RPE. RESULTS: The software substantially overestimated the very small (D=2.5 mm) nodule's volume [mean RVE: (100.8%±28%)] and underestimated it attenuation [mean AAE: (-756±80) HU]. The mean RVEs of nodule with diameter as 5 mm and 10 mm were small [(-0.9%±1.1%) vs (0.9%±1.4%)], however, the mean AAEs [(-243±26) HU vs (-129±7) HU)] were large. The ANOVA analysis for repeated measurements showed that different tube current and reconstruction algorithm had no significant effect on the volumetric measurements for nodules with diameter of 5 mm and 10 mm (F=5.60, P=0.10 vs F=11.13, P=0.08), but significant effects on the measurement of CT value (F=34.79, P<0.001 vs F=156.14, P<0.001). CONCLUSIONS: An infinitesimally small errors of volumetric measurement of 5 mm or 10 mm nodule could achieved with very low current and ASIR reconstruction, suggesting a possibility of remarkable radiation dose reductions, while it is not applicable for 5 mm nodule. The attenuation acquired through three dimensional software has large measurement error and can not applied in clinical currently.
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Effect of intestinal epithelial autophagy on bacterial translocation in severe acute pancreatitis.

BACKGROUND AND OBJECTIVE: We examined the impact of autophagy activation on bacterial translocation (BT) and tight junction (TJ) proteins in the intestinal mucosa of patients with severe acute pancreatitis (SAP). METHODS: Thirty-one SAP patients were divided into two groups, BT(+) and BT(-), according to the presence of BT in the blood, as detected by 16S rDNA sequencing. Eight healthy individuals were included in the control group. Serum endotoxin levels were measured by ELISA. Colonic mucosal tissue was obtained by endoscopy, and the TJ proteins and phosphatidylethanolamine-conjugated microtubule-associated protein light chain 3 (LC3-II) were analyzed using immunofluorescence and Western blotting. RESULTS: The expression of LC3II in patients with SAP was higher than that observed in healthy controls. Patients who tested positive for the presence of BT had a higher level of claudins-2 (CL-2) and a lower level of occludin and Zonula occluden-1 (ZO-1) than BT(-) patients. Moreover, the levels of LC3II in BT(-) patients was higher than that found in BT(+) patients, and occludin and ZO-1 were positively correlated with LC3II. CONCLUSIONS: Autophagy activation in the intestinal epithelial cells of patients with SAP and its effects on BT may act through enhancing para-cellular TJs.

Effect of ceramide-1-phosphate transfer protein on intestinal bacterial translocation in severe acute pancreatitis.

BACKGROUND AND OBJECTIVE: The aim of the study was to investigate the effects of ceramide-1-phosphate transfer protein (CPTP) on the intestinal epithelial tight junction proteins in patients with severe acute pancreatitis (SAP). METHODS: Fifty patients with SAP were classified into two groups according to the presence of bacterial translocation (BT) in the blood. Thirty healthy individuals were included in the control group. The presence of BT was analyzed by polymerase chain reaction. The expression of tight junction proteins and CPTP was determined using immunohistochemistry and western blotting. RESULTS: Bacterial DNA was detected in the peripheral blood of 62.0% of the patients with SAP. The expression of CPTP and tight junction proteins in SAP patients was lower than that in healthy controls. Among the patients with SAP, those positive for BT(+) showed a lower level of CPTP and occluding (OC) and zonula occludens-1 (ZO-1) expression and a higher level of IVA cPLA2 expression than BT(-) patients. Moreover, the expression of CPTP was significantly associated with ZO-1 and showed a negative correlation with expression of IVA cPLA2 in SAP-BT(+) patients. CONCLUSIONS: CPTP affects the expression of tight junction proteins and may protects the intestinal epithelial barrier by downregulating the expression of IVA cPLA2.