IFN-γ decreases PD-1 in T lymphocytes from convalescent COVID-19 patients via the AKT/GSK3ß signaling pathway.

Post-COVID-19 syndrome may be associated with the abnormal immune status. Compared with the unexposed age-matched elder group, PD-1 in the CD8+ T cells from recovered COVID-19 patients was significantly lower. IFN-γ in the plasma of COVID-19 convalescent patients was increased, which inhibited PD-1 expression in CD8+ T cells from COVID-19 convalescent patients. scRNA-seq bioinformatics analysis revealed that AKT/GSK3ß may regulate the INF-γ/PD-1 axis in CD8+ T cells from COVID-19 convalescent patients. In parallel, an IFN-γ neutralizing antibody reduced AKT and increased GSK3ß in PBMCs. An AKT agonist (SC79) significantly decreased p-GSK3ß. Moreover, AKT decreased PD-1 on CD8+ T cells, and GSK3ß increased PD-1 on CD8+ T cells according to flow cytometry analysis. Collectively, we demonstrated that recovered COVID-19 patients may develop long COVID. Increased IFN-γ in the plasma of recovered Wuhan COVID-19 patients contributed to PD-1 downregulation on CD8+ T cells by regulating the AKT/GSK3ß signaling pathway.

Exploring multidrug-resistant Klebsiella pneumoniae antimicrobial resistance mechanisms through whole genome sequencing analysis.

BACKGROUND: Antibiotic-resistant Klebsiella pneumoniae has emerged as a critical public health threat worldwide. Understanding the antimicrobial resistance mechanisms of multidrug-resistant K. pneumoniae (MDR-Kp) and its prevalence in time and space would provide clinical significance for managing pathogen infection. METHODS: Eighteen clinical MDR-Kp strains were analyzed by whole genome sequencing (WGS), and the antimicrobial resistance genes and associated resistance mechanisms were compared with results obtained from the conventional microbiological test (CMT). The sequence homology across strains in our study and those previously collected over time from a wide geographical region was assessed by phylogenetic analysis. RESULTS: MDR-Kp strains were collected from eighteen patients who had received empirical treatment before strain collection, with sputum (83.3%, 15/18) being the primary source of clinical samples. The commonly received treatments include ß-lactamase inhibitors (55.6%, 10/18) and carbapenems (50%, 9/18). Using CMT, we found that all 18 strains were resistant to aztreonam and ciprofloxacin, while 14 (77.8%) showed resistance to carbapenem. Polymyxin B and tigecycline were the only antibiotics to which MDR-Kp strains were sensitive. A total of 42 antimicrobial resistance mechanisms were identified by WGS, surpassing the 40 detected by the conventional method, with 25 mechanisms shared between the two techniques. Despite a 100% accuracy rate of WGS in detecting penicillin-resistant strains, the accuracy in detecting cephalosporin-resistant strains was only at 60%. Among all resistance genes identified by WGS, Klebsiella pneumoniae carbapenemase-2 (KPC-2) was present in all 14 carbapenem-resistant strains. Phenotypic analysis indicated that sequence type (ST) 11 isolates were the primary cause of these MDR-Kp infections. Additionally, phylogenic clustering analysis, encompassing both the clinical and MDR-Kp strains previously reported in China, revealed four distinct subgroups. No significant difference was observed in the sequence homology between K. pneumoniae strains in our study and those previously collected in East China over time. CONCLUSION: The application of WGS in identifying potential antimicrobial-resistant genes of MDR-Kp has demonstrated promising clinical significance. Comprehensive genomic information revealed by WGS holds the promise of guiding treatment decisions, enabling surveillance, and serving as a crucial asset in understanding antibiotic resistance.

Calorie-restricted diet mitigates weight gain and metabolic abnormalities in obese women with schizophrenia: a randomized controlled trial.

Background: Obesity is a prevalent health problem in patients with schizophrenia, and calorie restriction diet (CRD) achieved effective weight loss and metabolic improvement; however, these have not been rigorously evaluated in obese patients with schizophrenia. Objective: To measure the effects of CRD on weight loss and metabolic status in hospitalized obese women with schizophrenia during a 4-week period. Methods: Participants were randomly assigned to two groups in a 1:1 ratio. The intervention group (n = 47) was asked to follow a CRD and the control group (n = 48) a normal diet for 4 weeks. Outcomes of body weight, body composition, as well as metabolic parameters were measured at baseline and following the intervention period. Results: Forty-five participants completed the 4-week research in both the intervention and control groups. Compared to the normal diet, adherence to the CRD significantly decreased body weight (2.38 ± 1.30 kg), body mass index (0.94 ± 0.52 kg/m2), waist circumference (4.34 ± 2.75 cm), hip circumference (3.37 ± 2.36 cm), mid-upper circumferences, triceps skin-fold thickness, fat mass and free fat mass with large effect sizes (p = <0.001, ηp2 range between 0.145 and 0.571), as well as total cholesterol (0.69 ± 0.70 mmol/L) with a medium effect size (p = 0.028, ηp2 = 0.054). There were no differences between the CRD and control groups in terms of pre-post changes in triglycerides, high- and low-density lipoprotein-cholesterols, as well as systolic and diastolic blood pressures (p > 0.05). Conclusion: CRD is preventative of weight gain, but not apparent in intervention for metabolic status in hospitalized obese women with schizophrenia.Clinical trial registration: http://www.chictr.org.cn, ChiCTR-INR-16009185.

Dipeptidyl peptidase 4 inhibitor reduces tumor-associated macrophages and enhances anti-PD-L1-mediated tumor suppression in non-small cell lung cancer.

PURPOSE: The efficacy of immune checkpoint inhibitors such as programmed cell death ligand 1 (PD-L1) antibodies in non-small cell lung cancer (NSCLC) is limited, and combined use with other therapies is recommended. Dipeptidyl peptidase 4 (DPP4) inhibitors, a class of small molecule inhibitors, are highly effective for treating type 2 diabetes. Emerging evidence implicates DPP4 inhibitors as immunomodulators that modify aspects of innate and adaptive immunity. We evaluated the combination of a DPP4 inhibitor (anagliptin) and PD-L1 blockade in an NSCLC mouse model. METHODS: The effect of the combination of anti-PD-L1 and anagliptin was evaluated in subcutaneous mouse models of NSCLC. Tumor-infiltrating immune cells were analyzed by flow cytometry. Bone marrow-derived monocytes of C57BL/6 mice were isolated in vitro to examine the underlying mechanism of anagliptin on the differentiation and polarization of macrophage. RESULTS: Anagliptin dramatically improved the efficacy of PD-L1 antibody monotherapy by inhibiting macrophage formation and M2 polarization in the tumor microenvironment. Mechanistically, anagliptin suppressed the production of reactive oxygen species in bone marrow monocytes by inhibiting NOX1 and NOX2 expression induced by macrophage colony-stimulating factor, reduced late ERK signaling pathway activation, and inhibited monocyte-macrophage differentiation. However, the inhibitory effect was reactivated by lipopolysaccharide and interferon-gamma interacting with corresponding receptors during M1 macrophage polarization, but not M2. CONCLUSIONS: Anagliptin can enhance PD-L1 blockade efficacy in NSCLC by inhibiting macrophage differentiation and M2 macrophage polarization, and combination therapy may be a promising strategy for treating PD-L1 blockade therapy-resistant patients with NSCLC.

Sulfur: a neglected driver of the increased abundance of antibiotic resistance genes in agricultural reclaimed subsidence land located in coal mines with high phreatic water levels.

Due to the shallow burial of groundwater in coal mines with a high phreatic water level, a large area of subsidence lakes is formed after the mine collapses. Agricultural and fishery reclamation activities have been carried out, which introduced antibiotics and exacerbated the contamination of antibiotic resistance genes (ARGs), but this has received limited attention. This study analyzed ARG occurrence in reclaimed mining areas, the key impact factors, and the underlying mechanism. The results show that sulfur is the most critical factor impacting the abundance of ARGs in reclaimed soil, which is due to changes in the microbial community. The species and abundance of ARGs in the reclaimed soil were higher than those in the controlled soil. The relative abundances of most ARGs increased with the depth of reclaimed soil (from 0 to 80 cm). In addition, the microbial structures of the reclaimed and controlled soils were significantly different. Proteobacteria, was the most dominant microbial phylum in the reclaimed soil. This difference is likely related to the high abundance of sulfur metabolism functional genes in the reclaimed soil. Correlation analysis showed that the differences in ARGs and microorganisms in the two soil types were highly correlated with the sulfur content. High levels of sulfur promoted the proliferation of sulfur-metabolizing microbial populations such as Proteobacteria and Gemmatimonadetes in the reclaimed soils. Remarkably, these microbial phyla were the main antibiotic-resistant bacteria in this study, and their proliferation created conditions for the enrichment of ARGs. Overall, this study underscores the risk of the abundance and spread of ARGs driven by high-level sulfur in reclaimed soils and reveals the mechanisms.

Beneficial effects of konjac powder on lipid profile in schizophrenia with dyslipidemia: A randomized controlled trial.

BACKGROUND AND OBJECTIVES: Konjac powder has the effect of improving blood lipids in the general population, but there is no research on schizophrenic patients who are susceptible to dyslipidemia. The aim of our study is to evaluate the effects of konjac powder on blood lipid, glucose levels, body weight, and blood pressure in schizophrenia inpatients with dyslipidemia. METHODS AND STUDY DESIGN: After a two-week adaptation period, 76 people with schizophrenia were enrolled in a 30-day double-blind randomized controlled trial. The subjects in the experimental group were given a beverage containing konjac powder 30 minutes before each meal, whereas those in the control group were given a beverage containing resistant maltodextrin. RESULTS: The lipid profile, plasma glucose, blood pressure, and body weight were measured at baseline and at the end of 30-day treatment. Fiftynine subjects completed the study. There was a substantial decrease in total serum cholesterol in the experimental group, but an increase in the control group. Likewise, apolipoprotein B decreased in the experimental group but increased in the control group. CONCLUSIONS: We concluded that a diet supplemented with konjac powder may prevent the deterioration of dyslipidemia in people with schizophrenia, demonstrating its potential value in the treatment of metabolic disorders in schizophrenia as a new therapeutic method.

Expression of KIAA1456 in lung cancer tissue and its effects on proliferation, migration and invasion of lung cancer cells.

The expression of human transfer ribonucleic acid (tRNA) methyltransferase 9-like (KIAA1456) protein in lung cancer tissue and its effects on certain genes involved in the proliferation, migration and invasion of lung cancer cells were investigated. Immunohistochemistry was applied to stain lung cancer tissue and adjacent tissue sections of 90 lung cancer patients, so as to evaluate the difference in the expression level of KIAA1456 between two tissues. The correlation of KIAA1456 expression with clinicopathological parameters of lung cancer was analyzed. Kaplan-Meier survival curves were used to analyze the relationship between KIAA1456 and postoperative survival in patients with lung cancer. KIAA1456 gene was overexpressed in lung cancer cell lines (A549 and GLC-15), and the influence of KIAA1456 gene on the expression of cyclin D1, neural cadherin (N-cadherin) and epithelial cadherin (E-cadherin) and their involvement in lung cancer cell proliferation, migration and invasion were observed. Compared with that in adjacent tissue, the expression of KIAA1456 in lung cancer tissue was significantly decreased (p<0.05). The low expression of KIAA1456 in lung cancer tissue was clearly associated with pathological tumor (pT) stage, pathological node (pN) stage, tumor-node-metastasis (TNM) stage and pathological stage, but had no correlation with sex, age, tumor size or histology of the patient. KIAA1456 low expression was related with poor prognosis of the lung cancer patient. According to Western blotting, the overexpression of KIAA1456 in lung cancer cells could inhibit the expressions of cyclin D1 and N-cadherin, and promote the expression of E-cadherin. The results show that KIAA1456 expression was low in lung cancer tissue, and was associated with poor prognosis in patients and was an independent prognostic factor in patients with lung cancer. Thus, KIAA1456 can be used as a tumor suppressor gene in lung cancer, suppressing the proliferation, migration and invasion of lung cancer cells.

High Mobility Group Box Protein 1 Serves as a Potential Prognostic Marker of Lung Cancer and Promotes Its Invasion and Metastasis by Matrix Metalloproteinase-2 in a Nuclear Factor-κB-Dependent Manner.

Several studies have reported a significant role of high mobility group box protein 1 (HMGB1) in lung cancer. Nevertheless, there is a lack of knowledge regarding the expression of HMGB1 and its correlation with the clinicopathological features of lung cancer. In addition, the potential molecular mechanisms underlying the role of HMGB1 in lung cancer are still unknown. We therefore investigated the clinicopathological and prognostic significance as well as the potential role of HMGB1 in the development and progression of lung cancer. HMGB1 expression in the tumor tissues of the cohort correlated with clinicopathological features. Moreover, lung cell migration and invasion were significantly increased after treatment with HMGB1. The matrix metalloproteinase-2 (MMP-2) expression and activity were upregulated after treatment with HMGB1, while the upregulated expression of MMP-2 stimulated by HMGB1 in lung cancer cells was significantly reduced with the blockage of si-p65. These results indicated that HMGB1 expression was significantly associated with lung cancer progression. We also showed that HMGB1 promoted lung cancer invasion and metastasis by upregulating the expression and activity of MMP-2 in an NF-κB-dependent manner. Taken together, these data suggested that HMGB1 may be a potential prognosis and therapeutic marker for lung cancer.

Glycyrrhizin Suppresses the Growth of Human NSCLC Cell Line HCC827 by Downregulating HMGB1 Level.

Lung cancer has very high mortality and glycyrrhizin was found to significantly inhibit the growth of lung cancer cells in vitro and tissues in mice. However, the detailed inhibitory role of glycyrrhizin in the growth of lung cancer is still unclear. In this study, we first found that glycyrrhizin inhibited the growth of lung tumor in PDX mice. And high level of HMGB1 promoted the migration and invasion of lung cancer cells, which was suppressed by glycyrrhizin. Moreover, glycyrrhizin reduced the activity of JAK/STAT signaling pathway, which is the upstream regulator of HMGB1. Therefore, this study revealed a potential mechanism by which glycyrrhizin can inhibit the progression of lung cancer.

Effect of glucomannan on functional constipation in children: a systematic review and meta-analysis of randomised controlled trials.

BACKGROUND AND OBJECTIVES: Constipation, a common complaint in children, considerably affects the quality of life. This systematic review assessed the treatment effects of glucomannan on children with constipation by summarising evidence from previous randomised controlled trials (RCTs). METHODS AND STUDY DESIGN: A comprehensive electronic literature search was conducted for identifying eligible RCTs that evaluated the effectiveness of glucomannan. The results were reported as mean differences (MDs), standardised mean differences (SMDs), and risk ratios (RRs) with 95% confidence intervals (CIs). The primary outcome was the defecation frequency per week; the secondary outcomes were stool consistency and the rate of successful treatment. A metaanalysis was conducted using the random effects model. RESULTS: Three RCTs evaluating 122 participants were identified. Glucomannan use was associated with an increased frequency of defecation (3 trials; MD=1.40; 95% CI: 0.36-2.44, p=0.008); however, there were no significant differences in the outcomes of stool consistency (3 trials; SMD=0.48; 95% CI: -0.44 to 1.40, p=0.300) or the rate of successful treatment (2 trials; RR=1.36; 95% CI: 0.48-3.81, p=0.110). CONCLUSIONS: Glucomannan moderately increases the defecation frequency of children with constipation but is not associated with a reduction in stool consistency or overall improvement in the rate of successful treatment. However, these results should be cautiously interpreted because of the small sample size and the risk of products containing glucomannan need to be considered. Additional large-scale and well-designed RCTs are necessary to evaluate the efficacy and long-term safety of glucomannan.

Detection of plasmid-mediated AmpC ß-lactamase in Escherichia coli.

Escherichia coli (E. coli) is a common opportunistic pathogen for nosocomial infection. The aim of the study was to examine the phenotype, genotype and epidemiology of plasmid-mediated AmpC ß-lactamases in E. coli. In total, 96 clinical isolates of repeated E. coli were collected from different hospitals between August and October 2012. Using a cefoxitin disk diffusion method to identify the phenotype of AmpC ß-lactamases in E. coli, the plasmid was extracted, and multiplex polymerase chain reaction (PCR) was used to determine the amp gene. The PCR products were purified and sequenced. Of the 96 isolates strains, 43 strains were cefoxitin-resistant. Twelve (12.5%) isolates were detected to produce AmpC ß-lactamases with multiplex PCR, 11 strains carried DHA type ampC-resistant genes, and one strain carried ACC type ampC-resistant genes. In conclusion, the incidence of producing a plasmid-mediated AmpC enzyme of E. coli strains was relatively high. Therefore, antibiotics such as imipenem, a carbapenem, potentially serve as the treatment of choice for the infection.

Detection and genotype analysis of AmpC ß-lactamase in Klebsiella pneumoniae from tertiary hospitals.

The aim of the present study was to investigate the phenotype and genotype of plasmid-mediated AmpC (pAmpC) ß-lactamase in Klebsiella pneumoniae and its antibiotic resistance. A total of 130 non-repetitive clinical isolates of Klebsiella pneumoniae, obtained from tertiary hospitals, were phenotypically screened for pAmpC ß-lactamase production with the cefoxitin disk diffusion test. ß-lactamase genes in the screened isolates were detected using multiplex polymerase chain reaction (PCR); carbapenemase genes in pAmpC ß-lactamase-producing isolates that were resistant to imipenem were detected using PCR. Out of the 130 isolates of Klebsiella pneumoniae, 62 strains (47.7%) were resistant to cefoxitin, including 14 strains (10.8%) positive for pAmpC ß-lactamase (DHA type), among which 12 strains (85.7%) were susceptible to imipenem, and 2 strains, which were carrying Klebsiella pneumoniae carbapenemase (KPC)-2 gene, were resistant to imipenem. The pAmpC ß-lactamase-producing Klebsiella pneumoniae isolates from the tertiary hospitals were mainly of DHA-1 genotype, and the majority were susceptible to carbapenems; drug-resistant strains were associated with KPC-2 expression.

Detection of AmpC ß-lactamases in Acinetobacter baumannii in the Xuzhou region and analysis of drug resistance.

The aim of the present study was to determine the prevalence and related drug resistance of AmpC ß-lactamases in Acinetobacter baumannii in tertiary-level hospitals in the Xuzhou region in China. A total of 134 clinical isolates of non-repetitive Acinetobacter baumannii were collected from different hospitals in the Xuzhou region, and multiplex polymerase chain reaction (PCR) was employed to determine the genotype of AmpC. The PCR products were purified and sequenced. The susceptibility to antibiotics was tested using the biometrics automated microbiological-assay system, VITEK-2. Amongst the 134 isolated strains, 96 strains were found to produce AmpC ß-lactamases, and the positive rate was 72%, all of which carried acinetobacter-derived cephalosporinase (ADC) type AmpC resistance genes. The drug sensitivity tests indicated that the positive Acinetobacter baumannii strains were resistant to the majority of extended-spectrum ß-lactam antibiotics, but were only sensitive to polymyxin. In conclusion, the incidence of AmpC enzymes in Acinetobacter baumannii strains in tertiary-level hospitals in the Xuzhou area is relatively high, and resistance to the majority of extended-spectrum ß-lactam antibiotics may be related to the ADC type of AmpC.

Myocardial remodeling in rats with metabolic syndrome: role of Rho-kinase mediated insulin resistance.

Insulin resistance (IR) plays a critical role in metabolic syndrome (MS). Previous studies have demonstrated that activated ROCK is increased in MS patients. However, the effect of Rho-kinase (ROCK) on IR has not been definitely determined. Thus, the aims of the present study were to determine whether ROCK activation induces IR or affects myocardial structure and function, as well as the possible mechanisms underlying this process. Wistar rats fed high fat, high glucose and high salt diet sewed as model of MS and we used transmission electron microscopy, echocardiogram technology, and terminal deoxynucleotidyl transferase-mediated DNA nick-end labeling staining to identify any myocardial damage. The protein levels of MYPT-1 (characteristic of ROCK activation), IRS-1 and AKT were analyzed by immunohistochemistry and Western blotting. In hearts from MS rats, we found increased protein levels of phospho-MYPT-1 and phospho-IRS-1 (Ser307) and decreased phospho-AKT compared to levels in normal rats. In conclusion, the results suggest that ROCK-mediated IR is involved in the development of myocardial impairments in MS rats and that this effect is mediated probably via the IRS-1/PI3-kinase/AKT pathway.

Effects of ramipril on serum monocyte chemoattractant protein 1, interleukin-18, and interleukin-10 in elderly patients with acute coronary syndrome.

Acute coronary syndrome (ACS) is a clinical syndrome caused by acute myocardial ischemia and a severe stage of coronary atherosclerosis heart disease. The aim of this study was to clarify whether ramipril was a therapeutic agent against monocyte chemoattractant protein 1 (MCP-1), interleukin 18 (IL-18), and interleukin 10 (IL-10) in elderly patients with ACS. A total of 190 subjects including 72 elderly patients with ACS (78.1% male, mean age 67.12 +/- 5.06 years), 60 elderly patients with stable angina pectoris (76.9% male, mean age 68.00 +/- 4.52 years), and 58 healthy volunteers (77.8% male, mean age 65.96 +/- 4.18 years) were recruited into the study. Serum MCP-1, IL-10, and IL-18 were determined in 132 elderly patients by enzyme-linked immunosorbent assay (ELISA) before and after treatment with low doses of ramipril (2.5-5 mg/day), and were determined in 58 healthy volunteers. The levels of serum MCP-1 and IL-18 were much higher in elderly patients with ACS than those in elderly patients with SAP and healthy volunteers. After treating with ramipril, the levels of MCP-1 and IL-18 were decreased in elderly patients with ACS. Moreover, ramipril significantly increased serum IL-10 in elderly patients with ACS. Ramipril plays an important role in elderly patients with ACS. With decreasing MCP-1 and IL-18, it can ameliorate cytokine-associated cardiac damage. This study may provide a new recognition of angiotensin-converting enzyme inhibitor for the treatment of ACS.

Effects of alphavbeta6 gene silencing by RNA interference in PANC-1 pancreatic carcinoma cells.

BACKGROUND: Integrin alphavbeta6 is up-regulated in a variety of human carcinomas and plays a crucial role in tumor invasion and metastasis. However, the function of alphavbeta6 in pancreatic carcinoma and its potential role in gemcitabine resistance remain unknown. MATERIALS AND METHODS: Small interfering RNA (siRNA) targeting alphavbeta6 was constructed and transfected into PANC-1 cells. Effects of alphavbeta6 knockdown on cell proliferation, invasion, cell cycle progression, apoptosis and chemosensitivity to gemcitabine were investigated. RESULTS: Expression of alphavbeta6 in PANC-1 cells was markedly suppressed by siRNA. Silencing of alphavbeta6 expression significantly inhibited cell proliferation and invasiveness, resulted in cell cycle arrest, and induced cell apoptosis. More importantly, alphavbeta6 knockdown enhanced chemosensitivity to gemcitabine and increased gemcitabine-induced caspase-mediated apoptosis. CONCLUSION: These findings suggest a novel mechanism by which alphavbeta6 contributes to pancreatic carcinoma progression. The combination of alphavbeta6 silencing and gemcitabine treatment may provide an effective therapeutic strategy for highly resistant pancreatic carcinoma.

Vascular endothelial growth factor (VEGF) enhances gastric carcinoma invasiveness via integrin alpha(v)beta6.

Integrins play an important role in tumor metastasis induced by vascular endothelial growth factor (VEGF). However, in the case of gastric cancer, the precise role of VEGF in regulating integrin alphavbeta6 is unclear. In this study, we found that most of the alphavbeta6 integrin-positive gastric cancer tissues were also VEGF-positive. Furthermore, when gastric carcinoma cells were exposed to VEGF, expression of alphavbeta6 integrin was up-regulated and the extracellular signal-related kinase (ERK) pathway was activated. When integrin alphavbeta6 was blocked either with beta6 siRNA or anti-alphavbeta6 antibody, the migration of tumor cells normally induced by VEGF, as well as the activation of ERK, were markedly inhibited. Blocking the ERK signaling pathway significantly inhibited cell mobility. Taken together, the data suggest that VEGF is critical to the invasive process in human gastric cancer and that this occurs via up-regulation of integrin alphavbeta6 expression and activation of ERK.

Norcantharidin induces HT-29 colon cancer cell apoptosis through the alphavbeta6-extracellular signal-related kinase signaling pathway.

Norcantharidin has been used as an efficacious anticancer drug in China for many years, but its true mechanism remains poorly understood. Intriguingly, in an in vitro series study of anticancer drugs, we found that norcantharidin can effectively inhibit epithelial tumor cells from expressing integrin alphavbeta6. Our previous studies have confirmed that integrin alphavbeta6 is closely relevant to malignant epithelial cell tumor biology behavior, and it can promote cancer cells to invade and metastasize through a special alphavbeta6-extracellular signal-related kinase (ERK) direct signaling pathway. In this study, we investigated the relationship between the norcantharidin anticancer mechanism and integrin alphavbeta6. After HT-29 colon cancer cells were treated with norcantharidin, cell apoptosis increased remarkably. The expression of alphavbeta6 and the amount of p-ERK decreased substantially; simultaneously, the linkage between alphavbeta6 and ERK was barely detectable. However, the expression of other integrins and the levels of mitogen-activated protein kinase hardly changed. On these grounds, we presumed that norcantharidin induced HT-29 colon cancer cell apoptosis through the alphavbeta6-ERK signaling pathway. This finding elicited a novel strategy for targeting the whole alphavbeta6-ERK signal pathway, rather than simply blocking the combining site of alphavbeta6-ERK in colon cancer treatment.

Comparison of adenosine stress and dobutamine stress by real-time myocardial contrast echocardiography in detecting myocardium ischemia in dogs.

BACKGROUND: Real-time perfusion imaging (RTPI) using ultrasound contrast agents has shown good "accuracy" in detecting myocardial infarction, however its accuracy in the assessment of peri-infarct ischemia and stress echocardiography are not known. The aim of this study was to determine the accuracy of RTPI in assessment of peri-infarct ischemia during dobutamine and adenosine stress. METHODS: We employed the RTPI modality (Agilent and ATL Philips) in a canine model (18 dogs) of distal coronary occlusion and proximal coronary stenosis. Using coronary flow probe recordings, the physiologic significance of proximal coronary stenosis was established by confirming abolition of the coronary reserve. The contrast agent Optison was given as a slow bolus injection at baseline, during prolonged distal coronary occlusion, during adenosine bolus stress and during dobutamine stress. Triphenyltetrazolium chloride (TTC) staining was used to verify a distal infarction. RTPI recordings at baseline, the distal coronary occlusion and stress protocols were randomly mixed and reviewed blindly. RESULTS: In all but one dog, RTPI detected a distal infarct as small as 9% of the left ventricle. The sensitivity, specificity and overall diagnostic accuracy of RTPI in the detection of distal infarcts were: 94%, 89% and 92%, respectively. The sensitivity, specificity, and overall diagnostic accuracy of RTPI in the assessment of peri-infarction ischemia were 83%, 92% and 88% for adenosine stress and 95%, 86% and 91% for dobutamine stress, respectively. CONCLUSIONS: Even small distal infarcts can be detected by RTPI; peri-infarct ischemia can be accurately recognized by RTPI during stress; adenosine and dobutamine stress appear equally reliable in the RTPI evaluation of peri-infarct ischemia.