Betulin attenuates pneumolysin-induced cell injury and DNA damage

AIMS

Pneumolysin, a pore-forming toxin, is an important virulence factor of Streptococcus pneumoniae with multiple biological activity, such as cell lysis and DNA damage. Thus, targeting this toxin is alternative strategy for the treatment of S. pneumoniae infection.

METHODS AND RESULTS

Haemolysin assay was performed to identify the potential PLY inhibitor. The mechanism by which betulin, a natural compound from birch bark, against PLY was determined via MICs determination, western blot analysis and oligomerization analysis. Cytotoxicity and Immunofluorescence assays were further used to evaluate the protection of betulin against PLY-induced cell injury and DNA damage. Here, betulin, a natural compound from birch bark, was indentified as an effective inhibitor of PLY. Importantly, at the concentrations required for such inhibition, betulin has no influence on S. pneumoniae viability or PLY production. The interaction of betulin with PLY restrict the olgomerizaiton of this toxin and, thus, directly neutralizing the activity of PLY. Additionally, betulin treatment alleviate PLY induced cells injury and DNA damage in the co-culture system of PLY and A549 cells.

CONCLUSIONS

Betulin could be used as a promising leading compound against S. pneumoniae virulence by directly targeting PLY without antibacterial activity.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results presented in this work provided a novel strategy and candidate for S. pneumoniae infection.

THU0544 MULTIMODAL PHOTOACOUSTIC/ULTRASONIC IMAGING SYSTEM: A NEW IMAGING METHOD FOR EVALUATING RA

Background:

Photoacoustic imaging (PAI), a new imaging technique which can be integrating with ultrasound (US) imaging, has shown potential in visualizing small joints. We have developed a multimodal photoacoustic/ultrasound (PA/US) imaging system, equipped with a handheld probe, which can provide dual-wavelength PA/US imaging to identify the micro-vessels of the inflamed articular regions and measure the oxygenation level of human inflamed synovium.

Objectives:

To validate the potential value for RA of the imaging system.

Methods:

A total of 32 RA patients received PA/US examination on seven small joints (MCP2, MCP3, PIP2, PIP3, MTP2, MTP5, and wrist of the clinically dominant side). The 0-3 score was used to semi-quantify the PA and PD signals of the inflammatory articular lesions, and the sums of PA and PD scores (PA-sum and PD-sum) were utilized. The relative oxygen saturation (SO2) values of the inflamed regions were measured by calculating the ratio of PA signals at the wavelength of 750nm and 830nm. All the patients were classified to 3 PA+SO2 patterns (Pattern 1: no or minimal PA signals; Pattern 2: evident PA signals and hyperoxia; Pattern 3: evident PA signals and hypoxia). The correlations between imaging scores and laboratory data, as well as clinical scoring systems were assessed.

Results:

A total of 32 patients of RA were recruited aged from 25-71 years-old were examined. PD-sum had moderate correlation with the clinical scores (r=0.529, 0.546, 0.490, 0.493 for DAS28ESR, DAS28CRP, SDAI, CDAI), moderate correlations with TJC (r=0.575) and SJC (r=0.491), fair correlation with VAS (r=0.239), poor correlation with PGA (r=0.153), and moderate correlation with EGA (r=0.457). The PA-sum had substantial correlations with the clinical scores (r= 0.699, 0.746, 0.723, 0.736 for DAS28ESR, DAS28CRP, SDAI, CDAI), substantial correlations with TJC (r=0.787) and SJC (r=0.694), moderate correlations with VAS (r=0.544) and PGA (r=0.529), and substantial correlation with EGA (r=0.708).

Ten patients were classified as Pattern 1, 12 as Pattern 2, 9 as Pattern 3. The PA+ SO2 patterns presented substantial correlations with the clinical scores (DAS28ESR r=0.690, DAS28CRP r=0.782, SDAI r=0.805, CDAI r=0.799, SJC r=647, TJC r=0.676, respectively), substantial correlation with VAS (r=0.714), and moderate correlation with PGA (r=0.476) and EGA (r=0.502). Significant differences between those who were classified as hypoxia and hyperoxia with evident PA signals, were detected in VAS (p=0.020) and PGA (p=0.026).

Conclusion:

The PA-sum scores and the PA+SO2 patterns can be utilized as objective imaging parameters reflecting the disease activity of RA. PAI may serve as a supplement to conventional US examinations for RA patients.

References:

[1]Backhaus, M., et al., Evaluation of a novel 7-joint ultrasound score in daily rheumatologic practice: a pilot project. Arthritis Rheum, 2009. 61(9): p. 1194-201.

[2]Colebatch, A.N., et al., EULAR recommendations for the use of imaging of the joints in the clinical management of rheumatoid arthritis. Ann Rheum Dis, 2013. 72(6): p. 804-14.

Figure 1.

the photo of the multimodal PA/US imaging system

Figure 2.

an example of the PA/US imaging

Disclosure of Interests:

Chenyang Zhao: None declared, Qian Wang: None declared, Xixi Tao: None declared, Chen Yu: None declared, Sirui Liu: None declared, Mengtao Li: None declared, Xinping Tian: None declared, Zhenhong Qi: None declared, Jianchu Li: None declared, Fang Yang: None declared, Lei Zhu: None declared, Xiaofeng Zeng Consultant of: MSD Pharmaceuticals, Meng Yang: None declared, Yuxin Jiang: None declared

Macrophage Depletion Improves Chronic Rejection in Rats With Allograft Heart Transplantation

BACKGROUND

Macrophages may be important in chronic rejection after organ transplantation. This study aimed to investigate the possibility of depleting macrophages for a certain amount of time to alleviate chronic rejection in a heart transplant model of Fischer to Lewis rats.

METHODS

Clodronate liposome was injected abdominally to deplete macrophages for 2 time frames. The expression levels of ectodysplasin 1, arginase 1 (Arg1), chitinase-like lectin (Ym1), interferon gamma, tumor necrosis factor α (TNF-α), smooth muscle α-actin (α-SMA), monocyte chemoattractant protein 1 (MCP-1), and interleukin 10 (IL-10) were detected.

RESULTS

1. The expression levels of α-SMA, interferon gamma, TNF-α, and MCP-1 and the transformation of peripheral T cells were lower after macrophage depletion for 2 or 4 weeks. 2. The expression levels of α-SMA, TNF-α, and MCP-1 and the transformation of peripheral T cells were even lower after 4 weeks compared with 2 weeks, except for interferon gamma. 3. A higher level of expression of Arg1 and Ym1 after macrophage depletion for 2 weeks was observed. 4. A higher level of expression of IL-10 after macrophage depletion for 2 weeks, but not 4 weeks, was also observed.

CONCLUSIONS

Macrophage clearance after heart transplantation alleviated chronic rejection probably via M2 polarization of regenerated macrophages, reduced T-lymphocyte proliferation, and changed the expression levels of interferon gamma, TNF-α, MCP-1, and IL-10.

Anti-hydroxy-3-methylglutaryl-coenzyme A reductase (anti-HMGCR) antibody in necrotizing myopathy: treatment outcomes, cancer risk, and role of autoantibody level

Objective: To evaluate clinical associations of anti-hydroxy-3-methylglutaryl-coenzyme A reductase (anti-HMGCR) antibody (Ab) and statin exposure in necrotizing myopathy (NM) patients. Methods: NM without a known myositis-specific autoantibody (MSA) was ascertained from a large single-centre myositis database between 1985 and 2012. A comparison NM cohort included 32 anti-SRP⁺ autoantibody patients, and other control groups included 74 non-NM myositis patients and 21 non-myositis controls. Sera from all cases and controls were tested using a validated anti-HMGCR enzyme-linked immunosorbent assay. Clinical features including statin use and anti-HMGCR Ab status were compared between cases and controls. Results: Of the 256 NM muscle biopsies reviewed, only 48 subjects with available sera were identified as traditional MSA-negative NM. Anti-HMGCR positivity was significantly (p < 0.001) associated with MSA-negative NM [48% (23/48)] compared to all of the myositis and non-myositis controls [5% (6/127)]. Most anti-HMGCR Ab-positive NM patients had high titres of anti-HMGCR (83%) and a history of statin exposure (78%), along with severe muscle weakness, high creatine kinase (CK) levels (90% ≥ 5000 IU/L), a paucity of other organ manifestations, and the need for immunosuppression with prednisone and methotrexate, but generally favourable outcomes. Anti-HMGCR serum levels were associated with baseline CK levels but not muscle weakness. Conclusion: HMGCR Ab-positive NM patients are associated with statin exposure, have severe muscle weakness and high CK at presentation, lack other organ manifestations, and generally have favourable outcomes from immunosuppression. Anti-HMGCR Abs should be assessed in MSA-negative NM patients, particularly those with a history of statin exposure.

Understanding the Fertilizer Management Impacts on Water and Nitrogen Dynamics for a Corn Silage Tile-Drained System in Canada

Effective management of dairy manure is important to minimize N losses from cropping systems, maximize profitability, and enhance environmental sustainability. The objectives of this study were (i) to calibrate and validate the DeNitrification-DeComposition (DNDC) model using measurements of silage corn ( L.) biomass, N uptake, soil temperature, tile drain flow, NO leaching, NO emissions, and soil mineral N in eastern Canada, and (ii) to investigate the long-term impacts of manure management under climate variability. The treatments investigated included a zero-fertilizer control, inorganic fertilizer, and dairy manure amendments (raw and digested). The DNDC model overall demonstrated statistically "good" performance when simulating silage corn yield and N uptake based on normalized RMSE (nRMSE) < 10%, index of agreement () > 0.9, and Nash-Sutcliffe efficiency (NSE) > 0.5. In addition, DNDC, with its inclusion of a tile drainage mechanism, demonstrated "good" predictions for cumulative drainage (nRMSE < 20%, > 0.8, and NSE > 0.5). The model did, however, underestimate daily drainage flux during spring thaw for both organic and inorganic amendments. This was attributed to an underestimation of soil temperature and soil water under frequent soil freezing and thawing during the 2013-2014 overwinter period. Long-term simulations under climate variability indicated that spring applied manure resulted in less NO leaching and NO emissions than fall application when manure rates were managed based on crop N requirements. Overall, this study helped highlight the challenges in discerning the short-term climate interactions on fertilizer-induced N losses compared with the long-term dynamics under climate variability.

MicroRNA-30b inhibits non-small cell lung cancer cell growth by targeting the epidermal growth factor receptor

Lung cancer, especially non-small cell lung cancer (NSCLC), is the leading cause of cancer-related mortality in the world. Both microRNAs and epidermal growth factor receptor (EGFR) are important factors in NSCLC. In our study, the expression of miR-30b in 47 tumor tissues and paired normal tissues of NSCLC were detected by RT-PCR, and we found that miR-30b was down-regulated in NSCLC tumor tissues and was associated with TNM stage, differentiation, and lymph node metastases. Then we investigated the ability of miR-30b to regulate EGFR in several NSCLC cell lines, and found that miR-30b inhibited proliferation, migration and invasion, induced apoptosis and enhanced sensitivity of the NSCLC cells to EGFR tyrosine kinase inhibitors (EGFR-TKIs) by targeting EGFR and repressing EGFR signaling pathways. Overall, these results indicate that miR-30b may be a potential therapeutic target in NSCLC patients.

[Impact factor of postoperative prognosis of esophageal cancer patients with stage pT2N0~1M0]

Objective: To investigate the postoperative prognosis and the related factors of patients with stage pT2N0-1M0 of thoracic esophageal carcinoma(EC). Methods: From 2008 to 2011, clinical data of 275 cases with stage pT2N0-1M0 of thoracic EC treated by esophagectomy were enrolled. These cases includ 180 male and 95 female. Among them, 32 cases were upper thoracic EC, 186 cases were middle thoracic EC and 57 cases were lower thoracic EC. Alternatively, 205 cases were stage pN0, 70 cases were stage pN1. 155 cases received esophagectomy alone and 120 cases received esophagectomy and postoperative adjuvant therapy. Results: The end of follow-up time was on September 30th, 2014. The 1-, 3-, 5-year overall survival (OS) rates were 91.6%, 70.2% and 63.7%, respectively. The 1- 3-, 5-year progression-free survival (PFS) rates were 83.9%, 64.0% and 60.0%, respectively. The result of univariate analysis showed that the depth of tumor invasion, pathological type, pN stage and number of metastatic lymph nodes were significantly associated with OS (all of P<0.05). Moreover, the gender, the depth of tumor invasion, pathological type, pN stage and number of metastatic lymph nodes were significantly associated with PFS (all of P<0.05). Cox multivariate analysis showed that the location of primary tumor and pN stage were the independent factors of OS (both P<0.05). The gender, pN stage and postoperative adjuvant therapy were the independent factors of PFS (all of P<0.05). Conclusion: Among the patients with pT2N0~1M0 stage of thoracic EC, patients with upper thoracic EC or pN1 stage have poorer postoperative prognosis compared with others, and postoperative adjuvant treatment is recommended for these patients.

THE CORRELATION BETWEEN NECK CIRCUMFERENCE AND UMBILICAL ARTERY BLOOD FLOW IN PHYSIOLOGIC PREGNANCIES

Objective

To study the correlation between neck circumference(NC) and umbilical artery blood flow in physiologic pregnancies.

Methods

One hundred and one healthy pregnant woman in the third trimester were enrolled. Anthropometric measurements and ultrasonic testing were done.

Results

The women with NC ≥34.7cm had a more elevated umbilical artery pulsatility index(PI) and systolic/diastolic ratio (S/D) than the women with NC <34.7cm (P<0.01). NC were positively correlated with PI(r=0.224,P=0.024) and S/D ratio(r=0.415,P=0.0001). In multivariate analysis, NC was independently associated with PI (β=0.026, P=0.016) and S/D ratio (β=0.132, P=0.0001).

Conclusions

Obesity has an adverse impact on feto-placetal vessels, and NC was superior to body mass index.

Increased Expression of Programmed Cell Death-1 in Regulatory T Cells of Patients with Severe Sepsis and Septic Shock: An Observational Clinical Study

While regulatory T cells (Tregs) constitutively express programmed cell death-1 (PD-1), the role of PD-1 expression in Tregs of patients with sepsis remains unclear. Thus, we determined PD-1 expression in Tregs from the peripheral blood of patients with severe sepsis and septic shock. Seventy-eight patients with severe sepsis and 40 with septic shock, as well as 21 healthy subjects, were enrolled in this study. The percentage of peripheral blood PD-1⁺ Tregs, as well as absolute Treg counts, were compared between these three groups. PD-1 expression in Tregs and absolute Treg counts were also compared between survivors and non-survivors in patients with sepsis. PD-1 expression in Tregs increased in patients with sepsis compared to healthy controls. Conversely, absolute Treg counts were significantly decreased in patients with sepsis compared to healthy controls; patients with septic shock had the lowest absolute Treg counts. Among patients with sepsis, survivors had lower levels of PD-1 expression in Tregs, as well as higher absolute Treg counts, than non-survivors. Additionally, the percentage of PD-1⁺ Tregs correlated positively with lactate levels as well as the Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores in patients with sepsis. PD-1 was upregulated in Tregs of patients with sepsis and may indicate a state of immune dysfunction. Overexpression of PD-1 in Tregs was associated with more severe sepsis as well as poor outcomes.

[Patterns of recurrence in patients with stage Ⅲ thoracic esophageal squamous cell carcinoma after radical resection]

Objective: To evaluate the patterns of recurrence and their value on target delineation for postoperative radiotherapy (RT) in patients with stage Ⅲ thoracic esophageal squamous cell carcinoma (ESCC) after esophagectomy. Methods: 395 patients (302 male and 93 female) of stage Ⅲ thoracic ESCC after radical resection were enrolled in this study. Among them, 375 patients were treated with two-field and other 20 with three-field esopahgectomy. 97 patients were treated with surgery alone, 212 with adjuvant postoperative chemotherapy (CT), 56 with radiotherapy (RT) and 30 with CT plus RT. Diagnosis of recurrence was primarily based on CT images, some of which were biopsy confirmed. The location and patterns of tumor recurrence were analyzed. Results: The overall failure rates was 75.7% (299/395). Locoregional recurrence (LR) was found in 48.4% of the patients, distant metastasis (DM) in 16.2%, and LR plus DM in 4.3%. There were 208 patients occurred with LR, 26.9% (56) recurred in supraclavicular/neck (51 in supraclavicular), 69.7% (145) in mediastinum (88.7% in upper-mediastinum), and 19.7% (41) in upper abdomen (38 in para-aortic lymph node). Chi-square test and logistic multivariate regression analysis showed that TNM stage and adjuvant therapy were significantly associated with LR (P<0.05). Postoperative RT reduced LR (mainly LR in mediastinum), but postoperative CT did not decrease LR. Conclusions: The recurrence rate is very high in stage Ⅲ thoracic ESCC patients, LR is the main pattern of failure. TNM stage is one of the most important factors for LR. Postoperative radiotherapy can reduce LR but postoperative chemotherapy does not decrease LR. Upper-mediastinum is the most common site of recurrence, followed by supraclavicular and para-aortic regions; these areas should be considered as the key target of postoperative radiotherapy.

[Study of effects of micheliolide on ovarian cancer cell lines and its mechanism]

Objective: To study the roles of micheliolide on ovarian cancer cells. Methods: Firstly, human ovarian cancer cell lines HeyA8, SKOV3 and A2780/DDP were treated with different concentration of micheliolide(0.25, 0.5, 1, 2.5, 5, 10, 20, 50 μmol/L)for 72 hours, then methyl thiazolyl tetrazolium(MTT)assay was used wo detect the growth of the human ovarian cancer cell lines and the stongest inhibited cell line were selected for the following test. Secondly, after HeyA8 cell line was treated with different concentration(5, 10, 20 μmol/L)of micheliolide for 24 hours, the HeyA8 cell apoptosis was measured byflow cytometry. Thirdly, the expression of RelA mRNA in HeyA8 cell was detected through real-time PCR, the expressions of nuclear factor κB(NF-κB)signal pathway related protein RelA and the activited cysteinyl aspartate specific proteinase(caspase-9)were detected by western blot analysis. Results: (1)The growth of HeyA8, SKOV3 and A2780/DDP cells were all significantly inhibited after being treated with different concentration of micheliolide for 72 hours and the roles of inhibition were all concentration dependant(P<0.05). The half maximal inhibitory concentration(IC₅₀)of HeyA8, SKOV3 and A2780/DDP were(9.8±2.2),(12.0±2.1)and(12.8±1.8)μmol/L, respectively. We chose HeyA8 cell to do the following expreriments because of its best inhibited effect.(2)After HeyA8 cell was treated with micheliolide of different concentrations, as the concentration increased(20 and 0 μmol/L, for example), the apoptosis rate of HeyA8 cell raised from(7.2±1.0)% to(17.4±1.1)%, the percentage of survived cells reduce from(92.8 ± 1.3)% to(82.6 ± 1.4)%, and the relative mRNA level of RelA decreased from 1.00 ± 0.13 to 0.18 ± 0.00(P<0.01); furthermore, the expression of RelA protein was weaken and the activited caspase-9 protein expression was increased gradually. Conclusions: Micheliolide plays a significantly inhibited role in HeyA8, SKOV3 and A2780/DDP cells. The inhibited role of micheliolide inovarian cancer cells might through inhibiting nuclear factor-kappa B(NF-кB)signaling pathway, and inducing the expression of activited caspase-9 protein to promoting apoptosis of HeyA8 cell.

[Impact of number of dissected lymph nodes on survival in patients with thoracic esophageal squamous cell carcinoma after radical resection]

OBJECTIVE

To evaluate the impact of the number of dissected lymph nodes on survival of patients with stage T3N0M0 thoracic esophageal squamous cell carcinoma (ESCC).

METHODS

The clinicopathlogical dada of 249 patients with stage T3N0M0 thoracic ESCC were analyzed retrospectively. The median age of the 249 patients (171 males and 78 females) was 60-year old. The primary lesions were located in the upper- in 40, middle- in 177, and lower-thoracic esophagus in 45 patients. The median length of the lesions was 5 cm (range 2-12 cm). As for the severity of adhesion after surgery, there were 35 with no adhesion, 90 with mild-, and 124 patients with severe adhesion. The median number of dissected lymph nodes (dissected LN) at surgery was 9 (range 1-27), among them, less than 6 dissected LNs in 55, 6-11 dissected LNs in 133, and 11 or more dissected LNs in 61 cases. There were 210 patients with moderately or highly, and 39 with poorly differentiated cancer. 98 patients were treated with surgery alone, and 151 with postoperative adjuvant treatment.

RESULTS

The follow-up deadline was July 2013. The 1-, 3-, and 5-year overall survival rates were 90.0%, 68.7% and 55.2%, respectively. The 1-, 3-, and 5-year survival rates were 85.5%, 63.6% and 39.1% in patients with <6 dissected LNs, 89.5%, 67.7% and 56.9% in patients with 6-11 dissected LNs, and 95.1%, 75.4% and 66.2% in patients with >11 dissected LNs, respectively (P=0.073). The survival was shorter in patients with <6 dissected LNs than patients with >11 dissected LNs (P=0.022). The subgroup analysis showed that in patients with middle-thoracic ESCC, the length of lesion ≤5 cm or mild adhesion after surgery and the number of dissected LNs were associated with survival after surgery.

CONCLUSIONS

For patients with stage T3N0M0 thoracic ESCC after surgery, the number of dissected LNs is an important factor affecting the survival, and at least 6 or more lymph nodes should be dissected. If lymphadenectomy is not adequately performed, postoperative adjuvant therapy should be recommend.

Contact force-guided catheter ablation for the treatment of atrial fibrillation: a meta-analysis of randomized, controlled trials

Contact force (CF) sensing technology allows real-time monitoring during catheter ablation for atrial fibrillation (AF). However, the effect of CF sensing technology on procedural parameters and clinical outcomes still needs clarification. Because of the inconsistent results thus far in this area, we performed a meta-analysis to determine whether CF sensing technology can improve procedural parameters and clinical outcomes for the treatment of AF. Studies examining the benefits of CF sensing technology were identified in English-language articles by searching the MEDLINE, Web of Science, and Cochrane Library databases (inception to May 2015). Ten randomized, controlled trials involving 1834 patients (1263 males, 571 females) were included in the meta-analysis (681 in the CF group, 1153 in the control group). Overall, the ablation time was significantly decreased by 7.34 min (95%CI=-12.21 to -2.46; P=0.003, Z test) in the CF group compared with the control group. CF sensing technology was associated with significantly improved freedom from AF after 12 months (OR=1.55, 95%CI=1.20 to 1.99; P=0.0007) and complications were significantly lower in the CF group than in the control group (OR=0.50, 95%CI=0.29 to 0.87; P=0.01). However, fluoroscopy time analysis showed no significantly decreased trend associated with CF-guided catheter ablation (weighted mean difference: -2.59; 95%CI=-9.06 to 3.88; P=0.43). The present meta-analysis shows improvement in ablation time and freedom from AF after 12 months in AF patients treated with CF-guided catheter ablation. However, CF-guided catheter ablation does not decrease fluoroscopy time.

The effect of treadmill training and N-acetyl-l-cysteine intervention on biogenesis of cytochrome c oxidase (COX)

Mitochondrial biogenesis refers to increased content of mitochondria, which has been shown to be promoted by aerobic exercise. During this process, oxidative stress is considered the essential initiator. Even though some studies have addressed the issue as to whether antioxidants would hamper the effects of exercise on mitochondrial biogenesis, no consensus has been achieved. Therefore, the purpose of the present study was to investigate the effects of exercise and antioxidant intervention on mitochondrial biogenesis, as well as COX biogenesis. Thirty-two clean-grade male ICR mice were randomly assigned to a control group (Con), exercise group (Ex), N-acetyl-l-cysteine group (NAC), or NAC plus exercise group (NEx). The NAC and NEx groups were injected with NAC (0.1 mg/g/2 days) intraperitoneally for 3 weeks, whereas the Con and Ex groups were administered saline for the same period of time. Mice assigned to Ex and NEx groups started exercise training 1 week before drug intervention was initiated. After 1 week of acclimatization, the mice were allowed to run at a speed of 28 m/min for 60 min, 6 days a week. The results showed that exercise training caused an increase in mRNA and protein levels of COXIV, whereas NAC intervention lowered the two so significantly that even exercise training could not reverse the effect of NAC intervention. Our data suggest that even though antioxidant intervention could alleviate oxidative damage caused by exercise, it was not necessarily beneficial for mitochondrial biogenesis.