RESOLVE-based radiomics in cervical cancer: improved image quality means better feature reproducibility?

AIM: To compare the reproducibility of apparent diffusion coefficient (ADC)-based radiomic features between readout-segmented echo-planar diffusion-weighted imaging (RESOLVE) and single-shot echo-planar diffusion-weighted imaging (SS-EPI DWI) in cervical cancer. MATERIALS AND METHODS: The RESOLVE and SS-EPI DWI images of 36 patients with histopathologically confirmed cervical cancer were collected retrospectively. Two observers independently delineated the whole tumour on RESOLVE and SS-EPI DWI, and then copied them to the corresponding ADC maps. Shape, first-order, and texture features were extracted from ADC maps in the original and filtered (Laplacian of Gaussian [LoG] and wavelet) images. Thereafter, 1,316 features were generated in each RESOLVE and SS-EPI DWI, respectively. The reproducibility of radiomic features was assessed using intraclass correlation coefficient (ICC). RESULTS: In the original images, RESOLVE showed 92.86%, 66.67%, and 86.67% of features with excellent reproducibility in shape, first-order, and texture features, while SS-EPI DWI showed 85.71%, 72.22%, and 60% of features with excellent reproducibility, respectively. In the LoG and wavelet filtered images, RESOLVE had 56.77% and 65.32% of features with excellent reproducibility and SS-EPI DWI had 44.95% and 61.96% of features with excellent reproducibility, respectively. CONCLUSION: Compared with SS-EPI DWI, the feature reproducibility of RESOLVE was better in cervical cancer, especially for texture features. The filtered images cannot improve the feature reproducibility compared with the original images for both SS-EPI DWI and RESOLVE.

Factors influencing workplace social capital among registered nurses in China.

AIM: To examine the modifiable predictors and the level of workplace social capital, transformational leadership, emotional intelligence and organizational justice among registered nurses in Chinese hospitals. BACKGROUND: Workplace social capital is a relational network developed among nurses and other healthcare professionals that provides social support, and gives value to their working lives. Internationally, cultivating high levels of social capital is critical as it can help improve nurse satisfaction and care, and address nurse turnover. However, knowledge of factors influencing nurses' workplace social capital is limited in China. METHODS: In this cross-sectional, descriptive predictive study, 344 registered nurses were randomly selected from three urban Chinese hospitals in Zhejiang province. Five standard instruments were applied to collect data. Descriptive statistics were used to present the level of the variables and stepwise multiple regression was performed to identify the predictors of nurses' workplace social capital. RESULTS: Among eight potential factors, transformational leadership and emotional intelligence positively predicted workplace social capital. Nurses perceived the overall level of workplace social capital, emotional intelligence and unit managers' transformational leadership as high, and the overall level of organizational justice as moderate. DISCUSSION: Enhancing unit managers' transformational leadership and nurses' emotional intelligence was found to positively influence the development of workplace social capital. Although it is not a predictor of workplace social capital, nurses' organizational justice should be improved due to its importance and current unsatisfactory level. CONCLUSION AND IMPLICATIONS FOR NURSING AND HEALTH POLICY: Nursing and health policymakers need to consider the enhancement of transformational leadership and emotional intelligence when implementing policies to improve nurses' workplace social capital, nursing retention and job satisfaction.

LncRNA NEAT1 regulates proliferation, apoptosis and invasion of liver cancer.

OBJECTIVE: The occurrence and progression of hepatocellular carcinoma (HCC) is a multi-step complex process and the exact molecular mechanisms remain to be elucidated. LncRNA NEAT1 is involved in tumorigenesis and progression. However, the role of LncRNA NEAT1 in HCC remains unclear. PATIENTS AND METHODS: The tumor tissues and adjacent tissues of HCC patients were collected and LncRNA NEAT1 expression was detected by Real time PCR. The hepatoma cell line HepG2 was cultured and transfected with lnc RNA NEAT1 siRNA or lnc RNA NEAT1 plasmid followed by analysis of LncRNA NEAT1 expression, cell proliferation by MTT assay, as well as Caspase 3 activity. In addition, cell apoptosis and cell cycle were assessed by flow cytometry and cell invasion was measured by transwell chambers. The expression of EGFR, Bax and Bcl-2 was detected by Western blot. RESULTS: LncRNA NEAT1 expression was significantly increased in HCC tissues compared with adjacent tissues (p < 0.05). Compared with the siRNA group, transfection of lncRNA NEAT1 siRNA into HepG2 cells significantly inhibited cell proliferation, increased Caspase 3 activity and apoptosis, reduced cell invasion, as well as arrested cell cycle (p < 0.05). Meanwhile, lncRNA NEAT1 siRNA also significantly decreased Bcl-2 and EGFR expression and increased Bax expression (p < 0.05). Transfection of lncRNA NEAT1 plasmid in hepatoma cells HepG2 reversed the above changes, compared with vector group, the differences were statistically significant (p < 0.05). CONCLUSIONS: LncRNA NEAT1 expression is increased in liver cancer tissues. Down-regulation of LncRNA NEAT1 can inhibit EGFR expression and promote hepatoma cell apoptosis, inhibit cell cycle, thus inhibiting tumor proliferation and invasion.

Correlations between the expression of C-erB-2, CD34 and ER in breast cancer patients and the signs of conventional ultrasonography and ultrasound elastography.

OBJECTIVE: This study aims to investigate the correlations between the expression of human epidermal growth factor receptor 2 (C-erB-2), CD34, and estrogen receptor (ER) in breast cancer (BC) patients, and the signs of conventional ultrasonography and ultrasound elastography. PATIENTS AND METHODS: Clinical data of 88 patients who were pathologically diagnosed as breast cancer were retrospectively analyzed. HI VISION Avius color ultrasound device was used to perform ultrasound and related ultrasound parameters were analyzed. Expressions of C-erB-2, CD34, and ER were detected by immunohistochemistry. RESULTS: There was a correlation between positive expression of C-erB-2 and the blood supply, lymph node metastasis and microcalcification in patients (p < 0.05). Patients were divided into high expression group and low expression group according to the median expression level of CD34. Expression of CD34 was correlated with the ultrasound sign of lymph node metastasis (p < 0.05). Positive expression of ER was correlated with the morphology, margin, and perimeter of the tumor (p < 0.05). Expression levels of C-erB-2, CD34, and ER were found to be increased in BC patients. CONCLUSIONS: Combination of upregulated expression of C-erB-2, CD34, and ER and signs of ultrasound can improve the diagnosis of BC.

Ultra-low radiation dose CT angiography of the lower extremity using the iterative model reconstruction (IMR) algorithm.

AIM: To investigate the image quality of lower-extremity computed tomography (CT) angiography (CTA) with ultra-low radiation dose using the iterative model reconstruction (IMR) algorithm. MATERIALS AND METHODS: Lower-extremity CTA was acquired using a 256-multidetector CT system from 90 patients assigned into three groups: (1) the routine dose (RD) group: 120 kVp, automatic tube current modulation (ACTM) with an image quality index of 12, and filtered back projection (FBP); (2) the low-dose (LD) group: 80 kVp, ACTM with an image quality index of 1, and IMR; and (3) the ultra-low dose (ULD) group: 80 kVp, 20 mAs, and IMR. CT attenuation, image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the lower-extremity arteries were calculated. Subjective image quality of lower-extremity segments was assessed. Effective radiation dose was recorded. RESULTS: The radiation dose was reduced by 91.4% and 67.3% in the ULD group (0.15±0.02 mSv) compared to the RD group (1.86±0.51 mSv) and the LD group (0.49±0.08 mSv; both p<0.05). Higher CT attenuation, SNR, CNR, and lower image noise were obtained in the ULD group and the LD group compared to the RD group (all p<0.05). Better subjective image quality in lower leg segments was obtained in the ULD group and the LD group compared to the RD group (all p<0.05). No difference was found between the ULD and LD groups in both objective and subjective image quality (all p>0.05). CONCLUSION: By using IMR during lower-extremity CTA, the radiation dose is reduced by up to 91.4% without compromising image quality.

Primary antibiotic resistance of Helicobacter pylori in Chinese patients: a multiregion prospective 7-year study.

OBJECTIVES: To explore the characteristics of Helicobacter pylori resistance in China and the association between antibiotic resistance and several clinical factors. METHODS: H. pylori strains were collected from patients in 13 provinces or cities in China between 2010 and 2016. Demographic data including type of disease, geographic area, age, gender and isolation year were collected to analyse their association with antibiotic resistance. Antibiotic resistance was detected using the Etest test and the Kirby-Bauer disc diffusion method. RESULTS: H. pylori were successfully cultured from 1117 patients. The prevalence of metronidazole, clarithromycin (CLA), azithromycin, levofloxacin (LEV), moxifloxacin, amoxicillin (AMO), tetracycline and rifampicin resistance was 78.2, 22.1, 23.3, 19.2, 17.2, 3.4, 1.9 and 1.5%, respectively. No resistance to furazolidone was observed. The resistance rates to LEV and moxifloxacin were higher in strains isolated from patients with gastritis compared to those with duodenal ulcer and among women. Compared to patients ≥40 years old, younger patients exhibited lower resistance rates to CLA, azithromycin, LEV and moxifloxacin. The resistance rates to CLA and AMO were higher in strains isolated more recently, and we also found that the prevalence of resistance to metronidazole, CLA, azithromycin and AMO were significantly different among different regions of China. CONCLUSIONS: The resistance rates to metronidazole, CLA and LEV were high in China. Patient age, gender, disease and location were associated with the resistance of H. pylori to some antibiotics. Furazolidone, AMO and tetracycline are better choices for H. pylori treatment in China.

Uptake characteristics of levofloxacin for the eradication of Helicobacter pylori by GES-1 and MGC80-3 cells.

OBJECTIVE: The aim of this study was to study the uptake of levofloxacin for the eradication of Helicobacter pylori by human gastric epithelial cell lines, GES-1 and MGC80-3. MATERIALS AND METHODS: High performance liquid chromatography (HPLC) and coomassie brilliant blue staining, among other methods, were used to study the uptake of levofloxacin in GES-1 and MGC80-3 cells. The effect of time, concentration, temperature, pH, cyclosporine A, verapamil, and cimetidine on uptake was analyzed. RESULTS: The uptake of levofloxacin by GES-1 and MGC80-3 cells reached a steady state after 15 minutes of incubation, and was enhanced by increasing the extracellular levofloxacin concentration, although not in a linear manner. A maximum uptake was observed at 37 °C and pH 7.4. Cyclosporin A and verapamil enhanced uptake in GES-1 cells by 2.07%-13.23% (p > 0.05), and 17.5%-35.3% in MGC80-3 cells (p < 0.05). The uptake of levofloxacin was not affected by cimetidine. CONCLUSIONS: P-glycoprotein mediates levofloxacin uptake in MGC80-3 cell. Further, P-glycoprotein may be involved in levofloxacin uptake in GES-1 cells. However, organic cation transporters were not involved in levofloxacin uptake in MGC80-3 and GES-1 cells.

Patients with brain metastases derived from gastrointestinal cancer: clinical characteristics and prognostic factors

Purpose. This study seeks to evaluate the natural history, outcome, and possible prognostic factors in patients with brain metastases derived from gastrointestinal cancers. Methods. The clinical features, prognostic factors, and the effects of different treatment modalities on survival were retrospectively investigated in 103 patients with brain metastases derived from gastrointestinal cancers. Results. The median time from diagnosis of primary tumor to brain metastasis was 22.00 months. The interval between diagnosis of primary tumor relapse and brain metastasis was 8.00 months. The median follow-up time was 7.80 months. The median survival time after diagnosis of brain metastases was 4.10 months for all patients and 1.17 months for patients who received only steroids (36.9 %), 3.97 months for patients who only received whole-brain radiation therapy (WBRT 31.1 %), 11.07 months for patients who received gamma-knife surgery alone or/and WBRT (20.4 %), and 13.70 months for patients who underwent surgery and radiotherapy (12 patients, 11.6 %) (P < 0.001). Multivariate analysis revealed that recursive partitioning analysis (RPA) class, extracranial metastasis, and chemotherapy were independent prognostic factors. Brain metastasis derived from gastrointestinal tract cancer is rare, and overall patient survival is poor. Conclusion. RPA class, chemotherapy after brain metastases, and treatment regimens were independent prognostic factors for the survival of patients with brain metastases derived from gastrointestinal cancers (AU)

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Patients with brain metastases derived from gastrointestinal cancer: clinical characteristics and prognostic factors.

PURPOSE: This study seeks to evaluate the natural history, outcome, and possible prognostic factors in patients with brain metastases derived from gastrointestinal cancers. METHODS: The clinical features, prognostic factors, and the effects of different treatment modalities on survival were retrospectively investigated in 103 patients with brain metastases derived from gastrointestinal cancers. RESULTS: The median time from diagnosis of primary tumor to brain metastasis was 22.00 months. The interval between diagnosis of primary tumor relapse and brain metastasis was 8.00 months. The median follow-up time was 7.80 months. The median survival time after diagnosis of brain metastases was 4.10 months for all patients and 1.17 months for patients who received only steroids (36.9 %), 3.97 months for patients who only received whole-brain radiation therapy (WBRT 31.1 %), 11.07 months for patients who received gamma-knife surgery alone or/and WBRT (20.4 %), and 13.70 months for patients who underwent surgery and radiotherapy (12 patients, 11.6 %) (P < 0.001). Multivariate analysis revealed that recursive partitioning analysis (RPA) class, extracranial metastasis, and chemotherapy were independent prognostic factors. Brain metastasis derived from gastrointestinal tract cancer is rare, and overall patient survival is poor. CONCLUSION: RPA class, chemotherapy after brain metastases, and treatment regimens were independent prognostic factors for the survival of patients with brain metastases derived from gastrointestinal cancers.

Reconstructed metagenomes reveal changes of microbial functional profiling during PAHs degradation along a rice (Oryza sativa) rhizosphere gradient.

AIMS: The response of microbial metagenome to polycyclic aromatic hydrocarbons (PAHs) degradation in the rice rhizosphere remains poorly understood. We investigated the spatial and temporal variations of microbial communities and reconstructed metagenomes along the rice rhizosphere gradient during PAHs degradation. METHODS AND RESULTS: The experiment was performed in rhizoboxes, in which the rhizosphere region was divided into five 1-mm thick layers. Based on denaturant gradient gel electrophoresis profiling and sequencing of bacterial and archaeal 16S rRNA genes, predicted metagenomes were reconstructed. The microbial communities in the rice rhizosphere were influenced by the PAHs concentration and distance from the root surface during PAHs degradation. Correlation network analysis showed that archaea played an important role in PAHs degradation. Predicted metagenomes can be clustered into two groups with high and low PAHs degrading potential, respectively. The relative abundance of genes for defense mechanisms, replication, recombination and reparation was significantly higher in samples with high PAHs degrading potentials. The relative abundance of the dioxygenase gene was greater near the root surface of the rice. However, the abundance of aldolase and dehydrogenase was constant in rhizosphere soils at different distances from the root surface. CONCLUSIONS: Distance from root surface and PAH concentrations affected the microbial communities and metagenomes in rice rhizosphere. The abundance of dioxygenase genes relating to PAH degradation in metagenomes mirrored the PAH degradation potential in rice rhizosphere. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings suggested that the predicted metagenomes reconstructed from 16S rRNA marker gene sequences provide further insights into the spatial variation and dynamics of microbial functioning that occur during bioremediation.

Immediate effects of different schedules of somatostatin on portal pressure in patients with liver cirrhosis.

WHAT IS KNOWN AND OBJECTIVE: Somatostatin (SST) is used for the treatment of acute variceal bleeding based on its ability to decrease portal pressure and collateral blood flow. To date, no studies have focused on the immediate-early effects (between 1 and 30 min) of SST. The aim of this study was to compare the efficacy of different schedules of SST therapy with placebo on portal pressure in patients with portal hypertension treated with portal-azygous disconnection and to test whether an increase in bolus or infusion dose can improve the clinical efficacy of SST therapy. METHODS: Patients were treated with four different schedules: (a) standard dose (n = 11): one 250 µg bolus + a continuous infusion of 250 µg/h; (b) medium dose (n = 10): 500 µg bolus + a continuous infusion of 250 µg/h; (c) high dose (n = 10): 250 µg bolus + a continuous infusion of 500 µg/h; (d) control (n = 10): an injection of placebo (saline) followed by a placebo infusion. Following SST or placebo administration, portal pressure, central venous pressure (CVP), systemic blood pressure and heart rate (HR) were measured at 1, 3, 5, 7, 10 and 30 min. RESULTS AND DISCUSSION: The three schedules of SST induced a marked, rapid and highly significant decrease in portal pressure. The decline in portal pressure was moderate at 1 min (P < 0·040), achieved a peak effect at 5 min (P < 0·009) and remained decreased at 30 min. The effect of SST on portal pressure was significantly greater than placebo from 1 min after administration. There were no significant differences in portal pressure decrease between the three schedules of SST. The three schedules of SST and the placebo schedule did not induce significant changes in HR, systemic blood pressure and CVP. WHAT IS NEW AND CONCLUSION: This study shows that SST is effective in decreasing portal pressure within 30 min of administration in patients with liver cirrhosis. The clinical schedule used in this study was reasonable and safe.

Discrimination between neoplastic and non-neoplastic lesions in cirrhotic liver using contrast-enhanced ultrasound.

OBJECTIVES: To assess the value of contrast-enhanced ultrasound (CEUS) in differentiating hepatocellular carcinoma (HCC) from non-neoplastic lesion in cirrhotic liver in comparison with baseline ultrasound. METHODS: A total of 147 nodules (diameter ≤5.0 cm) in 133 cirrhotic patients (mean age±standard deviation: 52±13 years, range 20-82 years; gender: 111 males and 22 females) were examined with CEUS. There were 116 HCCs, 26 macroregenerative nodules and 5 high-grade dysplastic nodules. CEUS was performed with a real-time contrast-specific mode and a sulphur hexafluoride-filled microbubble contrast agent. RESULTS: Hypervascularity was observed in 94.8% (110/116) HCCs, 3.8% (1/26) macroregenerative nodules and 60.0% (3/5) high-grade dysplastic nodules during arterial phase on CEUS. Detection rates of typical vascular pattern (i.e. hypervascularity during arterial phase and subsequent washout) in HCCs with a diameter of ≤2.0 cm, 2.1-3.0 cm and 3.1-5.0 cm were 69.2% (27/39), 97.1% (33/34) and 100.0% (43/43), respectively. CEUS significantly improved the sensitivity [88.8% (103/116) vs 37.1% (43/116), p<0.001], negative predictive value [70.5% (31/44) vs 31.5% (29/92), p<0.001], and accuracy [91.2% (134/147) vs 49.0% (72/147), p<0.001] in differentiating HCCs from non-neoplastic lesions when compared with baseline ultrasound. However, the sensitivity and accuracy of CEUS for HCCs ≤2.0 cm in diameter were significantly lower than those for HCCs of 2.1-3.0 cm and 3.1-5.0 cm in diameter. CONCLUSIONS: CEUS improves diagnostic performance in differentiating HCCs from non-neoplastic nodules in cirrhotic patients compared with baseline ultrasound. Diagnosis of HCCs ≤2.0 cm diameter by CEUS is still a clinical concern, and thus needs further investigation.

Indoleamine 2,3-dioxygenase as a predictor of acute rejection after orthotopic liver transplantation in rat model.

BACKGROUND: Indoleamine 2,3-dioxygenase (IDO) had been reported to correlate with immunomodulatory effects and the severity of acute rejection (AR) after liver transplantation. We sought to study the time course of IDO mRNA expression in peripheral blood to diagnose AR. METHODS: The rats were divided into 4 groups each consisting of 32 rats: group A, isograft Sprague-Dawley (SD)-SD); group B, acute rejection model (SD-Wistar); group C, cyclosporine (CsA)-induced acceptance model (SD-Wistar rats treated with CsA, and group D, short-term CsA-treated model. The peripheral blood and liver tissue samples were obtained on the day of operation as well as 1, 2, 3, 4, 5, 7, and 9 days thereafter. We performed reverse-transcription polymerase chain reaction, pathologic studies, and serum tests. RESULTS: Groups A and C showed low levels of IDO mRNA as well as normal values of aspartate transaminase (AST), total bilirubin (T-BIL), and alkaline phosphatase (ALP) without AR. Group B showed a dramatic rise in IDO mRNA on day 2 with increased AST, T-BIL, and ALP at day 4 and mild AR on day 5. Group D, showed dramatically up-regulated IDO mRNA on day 4 with significantly increased AST, T-BIL, and ALP day 5 and mild AR detected on day 7. The expression of IDO gene in peripheral blood tightly correlated with the severity of acute rejection (P<.001). CONCLUSIONS: Compared with the pathologic study detection of IDO mRNA in peripheral blood diagnosed AR in the rat model at an earlier stage.

The role of oxidative stress in neuromelanin synthesis in PC12 cells.

Previous research has indicated that neuromelanin (NM) is involved in the pathogenesis of Parkinson's disease (PD). Increased reactive oxygen species (ROS) generation in PD sufferers is thought to be related to enhanced tyrosine hydroxylase (TH) activity and NM production. However, few reports have confirmed this hypothesis. In this study, PC12 cells of all experiments were exposed to 50 µmol/L levodopa (l-DOPA) to generate a model for NM synthesis. Meanwhile, PC12 cells were treated with glucose oxidase (GO) at different concentrations to generate oxidative stress. Finally, cell viability, TH activity, and NM generation in PC12 cells were measured. The results showed that GO dose-dependently stimulated oxidative stress generation in PC12 cells. Moderate increases in oxidative stress enhanced the viability of PC12 cells. However, an excessive level of oxidative stress can lead to the degeneration of PC12 cells. Notably, in the surviving PC12 cells, ROS significantly increased the TH activity, and the NM production was also upregulated. Thus, oxidative stress may upregulate the synthesis of NM, which may be a result of the increased TH activity observed in response to the elevated ROS in l-DOPA-treated PC12 cells.

Associations of the IL-1 and TNF gene polymorphisms in the susceptibility to duodenal ulcer disease in Chinese Han population.

Our aim was to investigate whether genetic polymorphism of IL-1Beta-511, IL-1RN, TNF-A-308 are involved in the susceptibility to duodenal ulcer (DU). 437 unrelated Chinese Han patients with DU and 148 healthy controls were genotyped by the polymerase chain reaction-restriction fragment length polymorphism method for the IL-1B-511, TNF-A-308 gene polymorphisms and the VNTR polymorphism in intron 2 of the IL-1RN gene polymorphisms. There was no difference in the genetic polymorphism of IL-1Beta-511, IL-1RN and TNF-A-308 in the patients with DU compared with control. After stratified by Helicobacter pylori infection, they also could not reach significant differences in this study. No statistically significant differences were observed in DU group compared with control according to combination of the IL-1Beta-511 and IL-1RN genotypes regardless of H. pylori positivity. These findings show that no evidence for the involvement of a proinflammatory polymorphism in the IL-1Beta-511, IL-1RN and TNF-A-308 in the susceptibility to DU in China.

Computerized endoscopic balloon manometry to detect esophageal variceal pressure.

BACKGROUND AND STUDY AIMS: Measuring the variceal pressure is important in predicting esophageal variceal bleeding. However, current noninvasive methods of measuring variceal pressure have not gained wide popularity. We have developed a computerized endoscopic balloon manometry (CEBM) system to detect variceal pressure. The aims of the study were to test the in-vitro accuracy of CEBM and to evaluate the clinical reliability and feasibility of this method. PATIENTS AND METHODS: The CEBM system, comprising an esophageal variceal manometer and a computer, records variceal pressure and manometry images simultaneously. In the in-vitro study, variceal models were fixed inside an artificial esophagus, into which an endoscope with transparent balloon was inserted for intraluminal pressure measurement. The artificial varix was filled with water and connected to a water column to modulate the intraluminal pressure. This CEBM system was tested blindly in variceal models with different intraluminal pressures. CEBM was also used to measure variceal pressure in 23 patients with liver cirrhosis and esophageal varices, and the results were compared with the hepatic venous pressure gradient (HVPG). RESULTS: In the in-vitro study, the measured intraluminal pressure correlated significantly with the actual intraluminal pressure for different diameters (R > or = 0.993, P < 0.001). Variceal pressure measurements with CEBM were technically successful in 23 patients. Regression analysis showed a good correlation between variceal pressure measured with CEBM and the HVPG (R = 0.858, P < 0.001). CONCLUSIONS: Our preliminary results indicate that CEBM is feasible and accurate. CEBM may become a more reliable method for detecting variceal pressure.

Induction of tumor necrosis-alpha, p38 and JNK in the spinal cord following acute heart injury in the rat model.

BACKGROUND: It is still not known whether the spinal cytokine signaling pathways are involved in the pathophysiologic mechanism of the acute phase of heart disease. This study examines the expression pattern of tumor necrosis factor-alpha (TNF-alpha) and its two related mitogenic-activated protein kinases, p38 and Jun-N-terminal kinase (JNK), in the spinal cord in response to acute cardiac injury (ACI). METHODS: The ACI rat model was established by intra-myocardial injection of formalin. At the indicated times after the establishment of ACI, the thoracic segments of the spinal cord were harvested and Western blot was performed to determine the expression of TNF-alpha, p38 and JNK. The localization of the cytokine and the kinases was determined by immunohistochemistry and double immunofluorescence. RESULTS: In response to ACI, TNF-alpha protein was up-regulated and reached a peak level at 6 h after ACI. The up-regulated TNF-alpha was distributed in all the laminae in the spinal cord and mainly localized in the neurons, as determined by immunohistochemistry and double immunofluorescence. In response to ACI, p38 and JNK were also up-regulated in the spinal cord. The expression profiles of p38 and JNK were similar to that of activated TNF-alpha following ACI. CONCLUSIONS: This study shows that cardiac injury can induce the activation of spinal TNF-alpha, p38 and JNK. The activated spinal cytokine signaling may contribute to disease progression in the acute phase of cardiac injury in clinical practice.

Change of nitric oxide in experimental colitis and its inhibition by melatonin in vivo and in vitro.

AIM: To investigate the change of nitric oxide (NO) in rat colitis and its inhibition by melatonin in vivo and in vitro. METHODS: In vivo, rat colitis was established intracolonically with trinitrobenzenesulphonic acid (TNBS) and ethanol. The animals were randomised into five groups: control group, model group, melatonin group (2.5, 5.0, 10.0 mg/kg), and treated intracolonically with saline, saline and melatonin respectively (once a day, from day 7 after colitis was established to day 28). After the end of the experiment, the mucosal damage index (CMDI) and histology score (HS) were evaluated and the level of myeloperoxidase (MPO) and malondiadehyde (MDA) and NO in the colon tissue were measured. In vitro, the co-culture model of the inflamed colon mucosa (from the colitis) with lipopolysaccharide (LPS), and the colonocytes oxidative injury model by hydroxyl radical, were designed respectively to elucidate the inhibition of NO by melatonin. RESULTS: After treated with TNBS/ethanol, the extent of CMDI and HS, the levels of MPO, MDA, and NO in the model group, were higher than that in the control group; melatonin ameliorated these parameters effectively. The stimulation of LPS increased the level of NO and MPO and MDA in the co-culture model of inflamed colon mucosa, and melatonin significantly reduced the level of MPO, MDA, and NO. In the coloncyte oxidative injury model by hydroxyl radical, the contents of LDH, MDA, and NO were increased; melatonin reversed this oxidative injury considerably. CONCLUSION: This study showed that TNBS/ethanol induced colitis was pharmacologically controlled by melatonin in vivo and in vitro.

Electronic transport in Y-junction carbon nanotubes

Electronic transport measurements were performed on Y-junction carbon nanotubes. These novel junctions contain a large diameter tube branched into smaller ones. Independent measurements using good quality contacts on both individual Y junctions and many in parallel show intrinsic nonlinear transport and reproducible rectifying behavior at room temperature. The results were modeled using classic interface physics for a junction with an abrupt change in band gap due to the change in tube diameter. These Y-junction tubes represent new heterojunctions for nanoelectronics.