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Radiation-induced heart disease (RIHD) is a serious side effect of radiotherapy for thoracic tumors. Advanced myocardial fibrosis in the late phase of RIHD can lead to myocardial remodeling, heart function impairing and heart failure, resulting in serious clinical consequences, and its pathogenesis remains vague. DNA methylation is one of the important epigenetic mechanisms which often occurs in response to environmental stimuli and is crucial in regulating gene expression. We hypothesized DNA methylation may contribute to pathogenesis in radiation-induced heart fibrosis (RIHF) and altered DNA methylation patterns probably influenced the genes expression in RIHF. In present study, we found genome-wide differences in DNA methylation status and RNA expression were demonstrated and we screened out 44 genes whose altered expression maybe were regulated by CpG island methylation within the gene promoter in RIHF of Sprague-Dawley rat by employing gene expression arrays and human CpG island microarrays. Gene expression and CpG island methylation levels of several candidate genes were further validated. Our investigation provided a new dimension to reveal the specific mechanisms of RIHF and explore the potential therapeutic targets for it., (©2022 by Radiation Research Society. All rights of reproduction in any form reserved.)

Cervical cancer is the second most common malignancy in women worldwide and always has recurrence owing to radioresistance. MicroRNA (miRNA or miR) has been identified to relate to the sensitivity of cancer radiotherapy. Here, we investigated the potential of miRNA-320 as a biomarker for radiosensitivity by targeting β-catenin in cervical cancer. A radioresistant cervical cancer cell line, C33AR, was established, and the radioresistance of C33AR cells was confirmed by a colony-formation assay. The expression of miRNA-320 was detected by reverse transcription-quantitative polymerase chain reaction, and compared between C33A and C33AR. β-catenin, the target of miRNA-320, was determined at the protein level by western blotting after transfecting the inhibitor of miRNA-320. The expression of miRNA-320 was markedly decreased in C33AR cells, which appeared to be more radioresistant, compared with its parental cell line C33A. Target prediction suggested that miRNA-320 negatively regulated the expression of β-catenin. Knockdown of β-catenin increased C33AR radiosensitivity, which revealed that the inhibition of β-catenin could rescue the miRNA-320-mediated cell radioresistance. On the other hand, overexpressing miRNA-320 increased C33AR radiosensitivity. In conclusion, miRNA-320 regulated the radiosensitivity of C33AR cells by targeting β-catenin. This finding provides evidence that miRNA-320 may be a potential biomarker of radiosensitivity in cervical cancer.

Cancer patients often suffer from local tumor recurrence after radiation therapy. Cell cycling, an intricate sequence of events which guarantees high genomic fidelity, has been suggested to affect DNA damage responses and eventual radioresistant characteristics of cancer cells. Here, we established a radioresistant lung cancer cell line, A549R , by exposing the parental A549 cells to repeated γ-ray irradiation with a total dose of 60 Gy. The radiosensitivity of A549 and A549R was confirmed using colony formation assays. We then focused on examination of the cell cycle distribution between A549 and A549R and found that the proportion of cells in the radioresistant S phase increased, whereas that in the radiosensitive G1 phase decreased. When A549 and A549R cells were exposed to 4 Gy irradiation the total differences in cell cycle redistribution suggested that G2-M cell cycle arrest plays a predominant role in mediating radioresistance. In order to further explore the possible mechanisms behind the cell cycle related radioresistance, we examined the expression of Cdc25 proteins which orchestrate cell cycle transitions. The results showed that expression of Cdc25c increased accompanied by the decrease of Cdc25a and we proposed that the quantity of Cdc25c, rather than activated Cdc25c or Cdc25a, determines the radioresistance of cells.

We have shown recently that sasanquasaponin (SQS) can inhibit ischemia/reperfusion-induced elevation of intracellular Cl(-) concentration ([Cl(-)](i)) and elicit cardioprotection by up-regulating anion exchanger 3 (AE(3)) expression. In the present study, we futher analysed the intracellular signal transduction pathways by which SQS up-regulates AE(3) expression and elicits cardioprotection. Cardiomyocytes were incubated for 24 h with or without 10 µmol/L SQS, followed by simulated ischemia/reperfusion (sI/R). NO formation, Ras activity, and extracellular-regulated kinase 1/2 (ERK1/2) phosphorylation were measured appropriately. We showed that SQS pretreatment efficiently attenuated viability loss and lactate dehydrogenase leakage induced by sI/R in cardiomyocytes. Moreover, SQS induced NO production and promoted Ras activation, which futher promoted extracellular-regulated kinase 1/2 (ERK1/2) phosphorylation. These effects were paralleled by an increase in AE(3) expression. However, when the cardiomyocytes were treated with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide (c-PTIO; an NO scavenger), S-trans-trans-farnesylthiosalicylic acid (FTS) (a Ras inhibitor), U0126 (an ERK1/2 inhibitor), respectively, the increase in AE(3) expression occurring during SQS pretreatment was almost completely abolished and, as a result, SQS-induced cardioprotection was prevented. Our findings indicate that SQS might up-regulate AE(3) expression through NO/Ras/ERK1/2 signal pathway to elicit cardioprotection in cultured cardiomyocytes.

Recent studies have shown that the cardioprotection of sasanquasaponin (SQS) against ischemia/reperfusion injury is related to inhibiting ischemia/reperfusion-induced elevation of intracellular Cl(-) concentration ([Cl(-) ](i)). However, the mechanism of inhibition remains unclear. Anion exchanger 3 (AE(3)) is an important regulatory protein for [Cl(-)](i). This study investigated whether AE(3) plays the critical role in the inhibitory effect of SQS on elevation of [Cl(-)](i) induced by ischemia/reperfusion and mediates the cardioprotection of SQS in H9c2 cells. Normal and AE(3) -knockdown H9c2 cells were incubated for 24 h with or without various concentrations of SQS (0.1, 1, or 10 µM) followed by simulated ischemia/reperfusion (sI/R). AE(3) expression was detected by Western blot. Flow cytometer analysis was employed to determine [Cl(-)](i,) [Ca(2+)](i) , reactive oxygen species (ROS) production, and cell apoptosis. The results showed that SQS pretreatment concentration-dependently attenuated sI/R-induced viability loss and lactate dehydrogenase leakage in normal H9c2 cells. Additionally, SQS concentration-dependently up-regulated AE(3) protein expression, and inhibited sI/R-induced the elevation of [Cl(-)](i) followed by the attenuation of Ca(2+) overload, ROS production, and cell apoptosis. However, the dose-dependent cardioprotection induced by SQS was abolished in AE(3) -knockdown H9c2 cells, and the inhibitory effects of SQS on [Cl(-)](i), Ca(2+) overload, ROS production, and cell apoptosis were also reversed. Our data indicate that AE(3) mediates the cardioprotective effect of SQS against sI/R injury. Importantly, AE(3) is required for SQS to inhibit sI/R-induced elevation of [Cl(-)](i), which subsequently inhibited sI/R-induced Ca(2+) overload, ROS production, and cell apoptosis., (Copyright © 2011 Wiley-Liss, Inc.)

The hydrophobicity of vertically aligned multiwalled carbon nanotubes (MWCNTs) was improved through the creation of a parallel array of microwalls via a laser pruning technique. Changes to the hydrophobic nature of the patterned MWCNTs due to artificially induced roughness through variations in both the widths of the walls and the distance between adjacent walls, channel width, were investigated. The sample became more hydrophobic whenever water droplets landed on one microwall 7 or 13 microm in width. However, when a droplet bridged two microwalls, the surface became less hydrophobic. The optimal superhydrophobic MWCNT surface corresponded to a parallel array of microwalls with a width of 13 microm and a channel width of approximately 50 microm. Such findings could possibly serve as value-add for further developments in the creation of water-repelling CNT surfaces via micropatterning.

Objective: To establish an animal model of Stanford type B aortic dissection using a two-end intimal flap suturing., Design: Twelve adult mongrel dogs of either sex were studied and followed up, at intervals, up to 1 year., Materials and Methods: A lateral clamp was placed on the proximal descending aorta after general anaesthesia and left thoracotomy. Half the circumference of the aorta, including the media and adventitia, was cut open transversely, leaving the intima intact. The aortic wall was separated inferiorly. The intima was transversely cut and both ends of the distal intimal flap were sutured to the adjacent aorta. To close, the distal adventitia and media were sutured to the proximal aorta. Before thoracic cavity closure, digital subtraction angiography (DSA) and colour Doppler ultrasound were performed., Results: Formation and distal extension was observed immediately after removal of the partial aortic clamp in 11 dogs. True and false lumens were seen in eight dogs; the false lumen was larger than the true lumen. Sacrifice at set intervals, 7 days to 12 months after surgery, showed a typical dissection tear, intima, septum, adventitia, thrombi and distal dissection blind pocket., Conclusion: This model of aortic dissection using the two-end aortic intimal flap suturing method is similar to human Stanford type B aortic dissection.

The investigations for selective adsorption of dibenzothiophene (DBT) over Ce/Ni-loaded Y zeolites with the emphasis on the effect of Ce as a cocation in the Ni-loaded Y zeolite are carried out in an attempt to produce more effective adsorbents for the desulfurization from transportation fuels. The promotional effects of Ce and coexisting toluene in the model fuel as well as contact time and adsorbent dose on the adsorptive performance were examined. The sulfur uptake strongly depends on the amount of Ce in the zeolite structure. The sorption data is varied according to both Langmuir and Freundlich isotherm models. The maximum sorption capacity by theoretically calculation is 22.2mg/g at 25 degrees C. The Langmuir constants b=5.82 mL/mg and the Freundlich constants K=1.042 L/mg and 1/n=0.4 are evaluated. Ni/Ce-loaded Y zeolites (NiCeY) and NiY, CeY, NaY zeolites were used as adsorbents for the removal of DBT from model fuel containing 500 mg/L sulfur with 5 vol% of toluene by a batch method under ambient conditions. NiCeY exhibits higher adsorptive selectivity for DBT than NiY and CeY, indicating that NiCeY is a more effective adsorbent to remove sulfur compounds from transportation fuels.

Objective: To evaluate the effect of the diameter of abdominal aortic aneurysm (AAA) on endovascular exclusion (EVE) and its results., Methods: From March 1997 to June 2007, 429 AAA patients were treated with endovascular stent-graft exclusion. According to the maximal diameter of abdominal aortic aneurysm, the patients were divided into two groups: group A (diameter < 55 mm, n = 274) and group B (diameter > or = 55 mm, n = 155). The diameter of AAA, involvement of iliac artery, length, diameter and distortion of aneurismal neck in the two groups were recorded and compared retrospectively., Results: Patients in group B were significantly older than group A (73.7 vs 71.1 years, P < 0.05). More patients in group B was complicated with coronary artery disease than those in group A (P < 0.05). The mean diameter of AAA in group A was (46.6 +/- 6.8) mm, and (66.8 +/- 11.2) mm in group B (P < 0.05). Proximal aneurysmal necks were shorter, wider and more tortuous in group B than those in group A (P < 0.05). Extraperitoneal approach, embolism of inner iliac artery and reconstruction of another inner iliac artery and stretch technique were more applied in group B. There were more endoleak during operation in group B and more stent-grafts were used. There was significant difference in morbidity rate between the two groups, while no statistic difference in mortality. And in group B, there were a high rate of endoleak and secondary intervention post operation., Conclusions: The diameter of AAA affects EVE and its results. In small aneurysms, EVE carries better outcome than in big aneurysms.

Background: Endovascular stent-grafting is widely used to treat thoracic aortic dissection. However, little information is available regarding outcome following simultaneous exclusion of multiple tears. This report details eight years of experience using simultaneous multi-tear exclusion for treatment of Stanford type B thoracic aortic dissection resulting in successful aortic remodeling without adverse events., Methods: From September 1998 to January 2006, 29 type B thoracic aortic dissection patients (24 men, 5 women; 27 chronic, 2 acute; mean age 58 years, range 45 - 77 years) were treated by simultaneous multi-tear exclusion in our center. Magnetic resonance angiography was used as the preoperative evaluation method. Different kinds of stent-grafts were used. The patients were followed up with contrast-enhanced spiral computed tomography at 6 months postoperatively and yearly thereafter., Results: Twenty-nine surgeries were completed successfully using at least 2 stent-grafts per patient (range: 2 - 6, mean: 2.7). No major procedure-related complications, such as rupture, paraplegia, aortic branch ischemia or cerebral infarction, were observed. During follow-up, favorable remodeling of the aorta was observed., Conclusions: The mid-term result of thoracic aortic dissection with simultaneous multi-tear exclusion was satisfactory. With the improvement of stent-grafts, simultaneous multi-tear exclusion should find wider application and become an optimal strategy for thoracic aortic dissection.

Objective: To evaluate the technical feasibility of juxtarenal abdominal aortic aneurysm (AAA) repair with fenestrated endovascular stent-graft, Methods: A 64-year-old male was diagnosed with juxtarenal AAA with severe coronary artery stenosis, fenestrations was customized according to precise helical CT data to accommodate visceral and renal arteries. Under general anesthesia and dynamic supervision of digital subtraction angiography (DSA), juxtarenal AAA was excluded with the customized fenestrated stent-graft and balloon expandable mini stent-grafts were deployed into bilateral renal arteries respectively., Results: After operation, DSA showed the patency of the super mesenteric artery, bilateral renal arteries and left hypogastric artery, no endoleak was found. The serum creatinine decreased slightly after operation. CT angiography revealed favorable morphology of the stent-graft without tortuosity, migration, disjoint and endoleak 10 days after the operation and patency of super mesenteric artery, bilateral renal arteries and left hypogastric artery., Conclusions: The placement of customized fenestrated endovascular stent-graft is a feasible option for juxtarenal AAA.

Background: Nitric oxide (NO) is an important mediator in the pathophysiology of many vascular diseases. However, the definite role of NO in human abdominal aortic aneurysm (AAA) formation is unclear. The aim of this study was to investigate production of NO and expression of inducible nitric oxide synthase (iNOS), and their possible role in AAA., Methods: A total of 28 patients with AAA, 10 healthy controls, and 8 patients with arterial occlusive disease were enrolled into this study. Standard colorimetric assay was used to examine NO concentration in plasma from patients with AAA and normal controls, and in cultured smooth muscle cells (SMCs). Expression of iNOS in aortas and cultured SMCs were detected by immunochemistry. The correlation of iNOS expression with age of the patient, size of aneurysm, and degree of inflammation was also investigated by Cochran-Mantel-Haenszel chi2 test and Kendall' Tau correlation., Results: Expression of iNOS increased significantly in the wall of aneurism in the patients with AAA compared to the healthy controls (P < 0.05) and the patients with occlusive arteries (P < 0.05). iNOS protein and media NOx (nitrite + nitrate) also increased in cultured SMCs from human AAA (n = 4, P < 0.05), while plasma NOx decreased in patients with AAA (n = 25) compared to the healthy controls (n = 20). There was a positive correlation between iNOS protein and degree of inflammation in aneurismal wall (Kendall coefficient = 0.5032, P = 0.0029)., Conclusions: SMCs and inflammatory cells were main cellular sources of increased iNOS in AAA, and NO may play a part in pathogenesis in AAA through inflammation.