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Thermal barrier coatings (TBCs) prepared using the atmospheric plasma spraying method fail mainly due to coating delamination caused by thermal mismatch in the absence of high temperature assessment. In this study, the thickness optimization of multiple ceramic layers in a TBCs and the influence of the interface structure on the residual stress of the coating were investigated using a finite element simulation method. The results showed that varying the thickness of each layer of a TBCs with multiple ceramic layers affects the distribution and magnitude of the residual stress of the coating. Therefore, a reasonable range of thickness for each layer can be determined. The thickness of the bonding layer should be 110 μm, the thickness of YSZ layer should be about 270 μm, the thickness of tantalate layer should be about 70 μm, and the thickness of Al2O3-YAG layer should be about 100 μm. Simultaneously, the results show that a rough interface can be more effective in reducing the relief of stress concentrations compared to a smooth interface, but the stress values increase.

Improving the catalytic efficiency in the hydration of olefins to alcohols is an important yet challenging issue in acid catalysis. Herein, a series of novel superacidic polyoxometalate-based ionic...

Nowadays, most available information on the degradative behaviour of feeds in ruminants is based on in situ incubation in the rumen, and it is adopted by many feed evaluation systems currently in use for ruminants. However, the outcome of this technique might be affected by many factors such as sequence of nylon bags incubation in the rumen. The objective of current study was to investigate effects of sequence of nylon bag incubation on degradative behavior of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) in some feed ingredients commonly used in dairy rations, including alfalfa haylage, corn silage, corn grain and soybean meal. Four multiparous Holstein lactating cows fitted with permanent ruminal cannulas were used. The nylon bags containing feed samples either were placed in the rumen at once and removed at designated time intervals (all in-gradually out method; AG) or were placed in the rumen at designated time points and retrieved at once (gradually in-all out method; GA). Fractional rate of degradation of potentially degradable fraction, lag time and effective rumen degradability (ED) of DM and CP were significantly higher in the AG compared to the GA method (P

A series of sulfonic functionalized ionic liquids (SFILs) with different acidity were designed and prepared for the synthesis of terpene esters (e.g. geranyl acetate). The effect of acidity of SFILs on their performance was investigated systematically. It is found that tuning the acidity of SFILs to an appropriate value results in not only high conversion of geraniol but also superior selectivity of geranyl acetate. The SFILs can be easily separated from products by filtration under room temperature, thus showing good reusability. Furthermore, the kinetics for SFILs in the esterification of geraniol were determined as the basis for future process design.

2-Hydroxyethylammonium acetate ionic liquid was found to be an excellent catalyst for the one-pot synthesis of 1,4-dihydropyridine derivatives via Hantzsch reaction of ethyl acetoacetate or acetoacetanilide, ammonium acetate, and various aromatic aldehydes. The combinatorial syntheses were achieved for the first time using 2-hydroxyethylammonium acetate ionic liquid as a homogeneous catalyst. The catalyst was active for the Hantzsch reaction in alcohol at reflux. The products were isolated in good yields (78–93 %). The resulting substituted dihydropyridines were characterized and confirmed by1H NMR spectral data. The catalyst offers simple means for recovery and the isolated catalyst was reused for three rounds for the synthesis without significant loss of catalytic activity. For all the other reactions carried out with the recycled catalyst, results were similar to that with the fresh catalyst.

Background Cholecystokinin (CCK), a gut hormone that is released during feeding, exerts gastrointestinal effects in part through vagal pathway. It is reported to be a potential trigger for increased postprandial visceral sensitivity in healthy subjects and, especially in patients with irritable bowel syndrome. NR2B-containing N-methyl-d-aspartate (NMDA) receptors in the central amygdala (CeA) participate in pain modulation. Systemically administered CCK activates the CeA-innervating neurons. Here, we investigated whether CCK modulation of visceral sensitivity is mediated through CeA NMDA-NR2B receptors and whether this modulation involves vagal pathway. Methods We first examined the visceromotor response (VMR) to colorectal distention (CRD) following i.p. injection of CCK octapeptide (CCK-8) in a rat model. Next, the NR2B antagonist ifenprodil and the NR2A antagonist NVP-AAM077 were microinjected into the CeA before systemic CCK injection. NR2B phosphorylation was detected by Western blot. To down-regulate NR2B gene expression, NR2B-specific small interfering RNA (siRNA) was delivered into CeA neurons by electroporation. In addition, the effects of functional deafferentation by perivagal application of capsaicin and pretreatment with the CCK1 receptor antagonist devazepide were investigated. Key Results CCK-8 increased VMR to CRD in a dose-dependent manner. This effect was blunted by intra-CeA administration of ifenprodil (but not NVP-AAM077) and was accompanied by phosphorylation of NR2B subunits in the CeA. CCK failed to increase VMR to CRD in NR2B siRNA-treated rats. Perivagal capsaicin application and pretreatment with devazepide prevented CCK-induced pronociception and CeA NR2B phosphorylation. Conclusions & Inferences The pronociception induced by systemic CCK, which is vagal afferent-dependent, requires activation of CeA NMDA-NR2B receptors.

Objective To observe the effects of quercetin on chronic mixed reflux esophagitis (RE) in rats by inhibiting the nuclear factor-κB p65 (NF-κBp65) and interleukin-8 (IL-8) signaling pathways. Methods Forty-eight healthy male Sprague–Dawley rats were randomly divided into six groups, with 8 rats in each group: the normal intact group, the sham operation group, the RE control group, the RE group treated with omeprazole or 100 mg/kg and 200 mg/kg quercetin. The animals were sacrificed after 6 weeks of different interventions. The pathological characteristics of esophageal mucosa were observed according to the diagnostic criteria and the expressions of NF-κBp65 and IL-8 were assessed by immunohistochemistry and real-time polymerase chain reaction. Results Compared with the RE control group, esophageal mucosal injury was improved and the expressions of NF-κBp65 and IL-8 were significantly decreased in the RE group treated with omeprazole or quercetin (P 0.05). There was no statistically significant difference between the RE groups treated with 100 mg/kg quercetin and 200 mg/kg quercetin. Conclusion Quercetin can prevent esophageal mucosal injury in RE rats by suppressing the NF-κBp65 and IL- 8 signaling pathways.

Objective To investigate the molecular mechanism of colorectal cancer (CRC) cell apoptosis induced by the Jumonji domain containing 2B (JMJD2B) silencing. Methods Both HCT116 and LoVo CRC cell lines were used for analyses. Cell apoptosis after JMJD2B silencing was determined by flow cytometry. JC-1 fluorescence probe was applied to measure the mitochondrial outer membrane permeabilization by flow cytometry and fluorescence microscopy. Immunofluorescence was used to detect cytochrome C translocation from mitochondria to cytosol after JMJD2B silencing. The efficacy of JMJD2B silencing on the protein levels of Bcl-2 family, caspase proteins, CCAAT/enhancer binding protein homologous protein (CHOP) and glucose-regulated protein 78 (GRP78) were detected by Western blot. Results JMJD2B silencing induced CRC cell apoptosis via a decrease of the anti-apoptotic gene Bcl-2 family expression, leading to the translocation of Bak and Bax proteins and the promotion of mitochondrial membrane disruption, resulting in the release of cytochrome C from mitochondria and subsequent caspase-9 and caspase-3 cleavage. It also increased the amount of cleaved caspase-8 involved in the death receptor-related apoptotic pathway. Bcl-2 homology 3 interacting-domain death agonist (Bid), a specific caspase-8 substrate involved in the Fas signaling pathway, subsequently induced cleavage via caspase-8 activation. However, levels of CHOP and GRP78 remained unchanged after JMJD2B silencing. Conclusions JMJD2B silencing induced CRC cell apoptosis via both mitochondria-related and death receptor-related pathways. The cleavage of Bid activated by caspase-8 might serve as a crosstalk mediator between these two pathways in CRC.

Estrogen reportedly facilitates visceral nociception at the spinal or supraspinal level. The present study was aimed to investigate whether estrogen modulates visceral pain through the vagal pathway. Ovariectomized rats received estradiol, which was administered subcutaneously (to act through both the vagal and spinal pathways) or intraduodenally (to preferentially act through the vagal pathway). Luminally applied estradiol induced a rapid and significant decrease in the visceromotor response to colorectal distension, with increased c-Fos expression in nodose ganglion neurons. Systemically injected estradiol increased visceromotor response and c-Fos expression in both nodose and dorsal root ganglion (T6-12) neurons. The antinociceptive effect of estrogen was abolished by surgical vagotomy or chemical denervation of vagal afferents. Both luminally and systemically administered estradiol elicited selective 5-hydroxytryptamine secretion from the duodenum. Granisetron, a 5-hydroxytryptamine 3 receptor antagonist, reversed the antinociceptive effect of estrogen. Intestinal mucosal mast cell stabilizers prevented estradiol-induced antinociception and 5-hydroxytryptamine secretion. Ultrastructural analysis revealed that estradiol caused piecemeal degranulation of intestinal mucosal mast cells. The actions of estradiol were inhibited by an estrogen receptor β antagonist and mimicked by an estrogen receptor β agonist. These results suggest that estrogen can trigger vagus-mediated antinociception, which is masked by its spinally mediated pronociception. Perspective This study is the first to show a vagus-mediated estrogenic antinociception, in which the nongenomic estrogen receptor β–mediated, intestinal mucosal mast cell–derived 5-hydroxytryptamine/5-hydroxytryptamine 3 receptor pathway is involved. This work may provide new insights into the sex hormone modulation of visceral sensitivity related to irritable bowel syndrome and indicate potential therapeutic targets to manage this disease.

2-Hydroxyethylammonium acetate ionic liquid was found to be an excellent catalyst for the one-pot synthesis of 1,4-dihydropyridine derivatives via Hantzsch reaction of ethyl acetoacetate or acetoacetanilide, ammonium acetate, and various aromatic aldehydes. The combinatorial syntheses were achieved for the first time using 2-hydroxyethylammonium acetate ionic liquid as a homogeneous catalyst. The catalyst was active for the Hantzsch reaction in alcohol at reflux. The products were isolated in good yields (78–93 %). The resulting substituted dihydropyridines were characterized and confirmed by1H NMR spectral data. The catalyst offers simple means for recovery and the isolated catalyst was reused for three rounds for the synthesis without significant loss of catalytic activity. For all the other reactions carried out with the recycled catalyst, results were similar to that with the fresh catalyst.

The unbalanced response and corresponding bifurcation behavior of the rotor dynamic system supported by gas journal bearings are investigated. A time-dependent mathematical model is used to describe the pressure distribution of gas journal bearing with nonlinearity. The rigid Jeffcott rotor with self-acting gas journal bearing supports is modeled. The finite difference method and the Successive Over Relaxation (S.O.R.) method are employed to solve the time-dependent Reynolds equation of gas journal bearings. The bifurcation of unbalanced responses of the rotor is analyzed by a Poincaré map. The numerical results reveal periodic, period-doubling, quasi-periodic, and chaotic motion of rich and complex non-linear behaviors of the system.

Background 5-HT1A receptors (HTR1As) in the insular cortex are thought to be related with the generation of stress-induced functional gastrointestinal disorders (FGIDs), but its mechanism is not clear. Visceral hypersensitivity is one important pathophysiological mechanism of FGIDs. This study aimed to explore the role of HTR1As in mediating stress-induced visceral hypersensitivity and its mechanism in the insular cortex. Methods Visceral hypersensitivity rat model was established by water avoidance stress (WAS) and the visceral sensitivity was measured by electromyogram. The activities of HTR1As were regulated by microinjecting the HTR1A agonist and antagonist into the insular cortex. The expression levels of 5-HT, HTR1A, N-methyl-d-aspartic acid receptor subtype 2B (NR2B) and c-fos were observed by RT-PCR, Western Blot and immunohistochemical staining. Key Results In WAS rats, the expression levels of 5-HT and HTR1As in the insular cortex were significantly lower (p < 0.05) than that in sham WAS and normal rats, but the levels of c-fos and NR2B were significantly higher (p < 0.05). After microinjecting HTR1As agonist into the insular cortex of WAS rats, the visceral sensitivity and the expression levels of NR2B and c-fos in insular cortex significantly decreased (p < 0.05). Conclusions & Inferences The HTR1As-NR2B signal pathway of insular cortex plays an important role in regulating stress-induced visceral hypersensitivity.

AIM: To explore whether clinician-patient communication affects adherence to psychoactive drugs in functional dyspepsia (FD) patients with psychological symptoms. METHODS: A total of 262 FD patients with psychological symptoms were randomly assigned to four groups. The patients in Groups 1-3 were given flupentixol-melitracen (FM) plus omeprazole treatment. Those in Group 1 received explanations of both the psychological and gastrointestinal (GI) mechanisms of the generation of FD symptoms and the effects of FM. In Group 2, only the psychological mechanisms were emphasized. The patients in Group 3 were not given an explanation for the prescription of FM. Those in Group 4 were given omeprazole alone. The primary endpoints of this study were compliance rate and compliance index to FM in Groups 1-3. Survival analyses were also conducted. The secondary end points were dyspepsia and psychological symptom improvement in Groups 1-4. The correlations between the compliance indices and the reductions in dyspepsia and psychological symptom scores were also evaluated in Groups 1-3. RESULTS: After 8 wk of treatment, the compliance rates were 67.7% in Group 1, 42.4% in Group 2 and 47.7% in Group 3 (Group 1 vs Group 2, P = 0.006; Group 1 vs Group 3, P = 0.033). The compliance index (Group 1 vs Group 2, P = 0.002; Group 1 vs Group 3, P = 0.024) with the FM regimen was significantly higher in Group 1 than in Groups 2 and 3. The survival analysis revealed that the patients in Group 1 exhibited a significantly higher compliance rate than Groups 2 and 3 (Group 1 vs Group 2, P = 0.002; Group 1 vs Group 3, P = 0.018). The improvement in dyspepsia (Group 1 vs Group 2, P < 0.05; Group 1 vs Group 3, P < 0.05; Group 1 vs Group 4, P < 0.01) and psychological symptom scores (anxiety: Group 1 vs Group 2, P < 0.01; Group 1 vs Group 3, P < 0.05; Group 1 vs Group 4, P < 0.01; depression: Group 1 vs Group 2, P < 0.01; Group 1 vs Group 3, P < 0.01; Group 1 vs Group 4, P < 0.01) in Group 1 were greater than those in Groups 2-4. The compliance indices were positively correlated with the reduction in symptom scores in Groups 1-3. CONCLUSION: Appropriate clinician-patient communication regarding the reasons for prescribing psychoactive drugs that emphasizes both the psychological and GI mechanisms might improve adherence to FM in patients with FD.

To observe the effects of quercetin on chronic mixed reflux esophagitis (RE) in rats by inhibiting the nuclear factor-κB p65 (NF-κBp65) and interleukin-8 (IL-8) signaling pathways.Forty-eight healthy male Sprague-Dawley rats were randomly divided into six groups, with 8 rats in each group: the normal intact group, the sham operation group, the RE control group, the RE group treated with omeprazole or 100 mg/kg and 200 mg/kg quercetin. The animals were sacrificed after 6 weeks of different interventions. The pathological characteristics of esophageal mucosa were observed according to the diagnostic criteria and the expressions of NF-κBp65 and IL-8 were assessed by immunohistochemistry and real-time polymerase chain reaction.Compared with the RE control group, esophageal mucosal injury was improved and the expressions of NF-κBp65 and IL-8 were significantly decreased in the RE group treated with omeprazole or quercetin (P 0.05). Compared with the omeprazole group, the gross and microscopic scores of esophageal mucosal injury and the expressions of NF-κBp65 and IL-8 in the 100 mg/kg and 200 mg/kg quercetin groups were not increased (P 0.05). There was no statistically significant difference between the RE groups treated with 100 mg/kg quercetin and 200 mg/kg quercetin.Quercetin can prevent esophageal mucosal injury in RE rats by suppressing the NF-κBp65 and IL- 8 signaling pathways.

To investigate the molecular mechanism of colorectal cancer (CRC) cell apoptosis induced by the Jumonji domain containing 2B (JMJD2B) silencing.Both HCT116 and LoVo CRC cell lines were used for analyses. Cell apoptosis after JMJD2B silencing was determined by flow cytometry. JC-1 fluorescence probe was applied to measure the mitochondrial outer membrane permeabilization by flow cytometry and fluorescence microscopy. Immunofluorescence was used to detect cytochrome C translocation from mitochondria to cytosol after JMJD2B silencing. The efficacy of JMJD2B silencing on the protein levels of Bcl-2 family, caspase proteins, CCAAT/enhancer binding protein homologous protein (CHOP) and glucose-regulated protein 78 (GRP78) were detected by Western blot.JMJD2B silencing induced CRC cell apoptosis via a decrease of the anti-apoptotic gene Bcl-2 family expression, leading to the translocation of Bak and Bax proteins and the promotion of mitochondrial membrane disruption, resulting in the release of cytochrome C from mitochondria and subsequent caspase-9 and caspase-3 cleavage. It also increased the amount of cleaved caspase-8 involved in the death receptor-related apoptotic pathway. Bcl-2 homology 3 interacting-domain death agonist (Bid), a specific caspase-8 substrate involved in the Fas signaling pathway, subsequently induced cleavage via caspase-8 activation. However, levels of CHOP and GRP78 remained unchanged after JMJD2B silencing.JMJD2B silencing induced CRC cell apoptosis via both mitochondria-related and death receptor-related pathways. The cleavage of Bid activated by caspase-8 might serve as a crosstalk mediator between these two pathways in CRC.

The NR2B subunit of NMDA receptor in the anterior cingulate cortex (ACC) is up-regulated in viscerally hypersensitive (VH) rats induced by colonic anaphylaxis. It plays a critical role in modulation of ACC sensitization and visceral pain responses. Given the key role of calcium/calmodulin-dependent protein kinase II (CaMKII) in synaptic plasticity and behavior learning and memory, we hypothesize that phosphorylation of CaMKII binding to NR2B mediates visceral pain in VH states. We performed in vivo electroporation of CaMKII siRNA produced inhibition of colorectal distension-induced visceromotor response in the VH rats. The NR2B, CaMKII and P-CaMKII-Thr²⁸⁶ protein levels were increased in 180%, 220% and 304% fold in the post-synaptic density (PSD) fraction in VH rats separately. Western blotting following co-immunoprecipitation showed that P-CaMKII-Thr²⁸⁶ bound to NR2B in the PSD, which was increased to 267% of control in VH rats. Administration of CaMKII antagonist Antennapedia-CaMKIINtide suppressed visceromotor response in VH rats in parallel with decrease of NR2B levels and reduction of the NR2B-P-CaMKII-Thr²⁸⁶ protein complex in PSD. In conclusion, CaMKII is a critical signaling molecule in the ACC glutamatergic synaptic transmission and phosphorylation of CaMKII at Thr286, which binds to NR2B subunit at post-synaptic site, modulates visceral pain in viscerally hypersensitive state.

AIM: To investigate the incidence of nocturnal dyspeptic symptoms in patients with functional dyspepsia (FD) and whether prokinetic drugs can alleviate them. METHODS: Eighty-five consecutive Chinese patients with FD were included in this study. One week after single-blinded placebo run-in treatment, baseline nocturnal intragastric pH, bile reflux and nocturnal dyspeptic symptoms of eligible patients, including epigastric pain or discomfort, abdominal distention and belching, were investigated with questionnaires. Patients exhibiting nocturnal dyspeptic symptoms were randomly and double-blindly assigned to domperidone group or placebo group. Nocturnal intragastric pH and percentage of duodenogastric bile reflux time were determined after treatment. RESULTS: Of the 85 FD patients, 2 females without nocturnal symptoms, who responded to placebo run-in treatment, were excluded from the study, 30 (36.1%) exhibited nocturnal dyspeptic symptoms with increased duodenogastric bile reflux time (intragastric bilirubin absorbance > 0.14) and mean gastric pH (confirming the existence of bile reflux) (P = 0.021, 0.023) at night were included in the study. Of these 30 patients, 21 (70%) had overt nocturnal duodenogastric bile reflux, which was significantly higher than that of those without nocturnal symptoms (P = 0.026). The 30 patients were allocated to domperidone group or placebo group (n = 15). The nocturnal duodenogastric bile reflux and gastric pH were significantly decreased after domperidone treatment (P = 0.015, 0.021). The severity score of nocturnal dyspeptic symptoms was also significantly decreased after domperidone treatment (P = 0.010, 0.015, 0.026), which was positively correlated with the reduced nocturnal bile reflux or gastric pH (r = 0.736, 0.784, 0.753 or r = 0.679, 0.715, 0.697, P = 0.039, 0.036, 0.037 or P = 0.043, 0.039, 0.040). CONCLUSION: A subgroup of Chinese FD patients show overt nocturnal dyspeptic symptoms, which may be correlated with the excessive nocturnal duodenogastric bile reflux. Domperidone therapy can alleviate these symptoms.

AIM: To investigate the influences of bile reflux on profiles of gastric mucosal lesions in patients with dyspepsia or chronic gastritis. METHODS: A total of 49 patients diagnosed with dyspepsia and chronic gastritis underwent 24-h ambulatory and simultaneous monitoring of intragastric bilirubin absorbance and pH values, and then they were divided into bile reflux positive group and bile reflux negative group. Severity of pathological changes in gastric mucosa including active inflammation, chronic inflammation, intestinal metaplasia, atrophy and dysplasia as well as Helicobacter pylori (H pylori) infection at the corpus, incisura and antrum were determined respectively according to update Sydney system criteria. The profiles of gastric mucosal lesions in the two groups were compared, and correlations between time-percentage of gastric bilirubin absorbance >0.14 and severity of gastric mucosal lesions as well as time-percentage of gastric pH >4 were analyzed respectively. RESULTS: Thirty-eight patients (21 men and 17 women, mean age 44.2 years, range 25-61 years) were found existing with bile reflux (gastric bilirubin absorbance >0.14) and 11 patients (7 men and 4 women, mean age 46.2 years, range 29-54 years) were bile reflux negative. In dyspepsia patients with bile reflux, the mucosal lesions such as active inflammation, chronic inflammation, intestinal metaplasia, atrophy or H pylori infection in the whole stomach, especially in the corpus and incisura, were significantly more severe than those in dyspepsia patients without bile reflux. Moreover, the bile reflux time was well correlated with the severity of pathological changes of gastric mucosa as well as H pylori colonization in the near-end stomach, especially in the corpus region. No relevance was found between the time of bile reflux and pH >4 in gastric cavity. CONCLUSION: Bile reflux contributes a lot to mucosal lesions in the whole stomach, may facilitate H pylori colonization in the corpus region, and has no influence on acid-exposing status of gastric mucosa in patients with dyspepsia or chronic gastritis.