ABSTRACT
In-stent restenosis (ISR) develops primarily due to neointimal hyperplasia. Gallic acid (GA) has anti-inflammatory, antioxidant, and cardioprotective effects. This study sought to investigate the effects of GA on neointimal hyperplasia and proliferation and migration of vascular smooth muscle cells (VSMCs) in a pig ISR model. In vitro proliferation and migration experiments were confirmed, after VSMCs were treated with platelet-derived growth factor (PDGF-BB) and GA (100 µM) using a 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay and a scratch wound assay for 24 hours and 48 hours. A bare metal stent (BMS) was implanted in the pig coronary artery to induce ISR with overdilation (1.1-1.2:1), and GA (10 mg/kg/day) was administered for 4 weeks. At the 4-week follow-up, optical coherence tomography (OCT) and histopathological analyses were performed. GA decreased the proliferation of VSMCs by PDGF-BB for 24 hours (89.24±24.56% vs. 170.04±19.98%, p<0.001) and 48 hours (124.87±7.35% vs. 187.64±4.83%, p<0.001). GA inhibited the migration of VSMCs induced by PDGF-BB for 24 hours (26.73±2.38% vs. 65.38±9.73%, p<0.001) and 48 hours (32.96±3.04% vs. 77.04±10.07%, p<0.001). Using OCT, % neointimal hyperplasia was shown to have significantly decreased in the GA group compared with control vehicle group (28.25±10.07% vs. 37.60±10.84%, p<0.001). GA effectively reduced neointimal hyperplasia by inhibiting the proliferation and migration of VSMCs in a pig ISR model. GA could be a potential treatment strategy for reducing ISR after stent implantation.
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BACKGROUND: Coronary artery disease is a cardiovascular disease with a high mortality and mortality rate in modern society. Vascular stent insertion to restore blood flow is essential to treat this disease. A fully biodegradable vascular scaffold (BVS) is a vascular poly (L-lactic acid) (PLLA) stent that is receiving growing interest as this is biodegradable in the body and does not require secondary removal surgery. However, acidic byproducts composed of PLLA produced during the biodegradation of the BVS can induce an inflammatory response. Magnesium hydroxide, a basic inorganic particle, neutralizes the acidic byproducts of PLLA. METHODS: In this study, we investigated using a BVS coated with everolimus and surface-modified magnesium hydroxide that suppresses smooth muscle cell proliferation and protects endothelial cells, respectively. The various characteristics of the functional stent were evaluated using in vitro and in vivo analyses. RESULTS: The BVS was successfully prepared with evenly coated everolimus and surface-modified magnesium hydroxide. A neutral pH value was maintained by magnesium hydroxide during degradation, and everolimus was released for one month. The coated BVS effectively inhibited protein adsorption and platelet adhesion, demonstrating excellent blood compatibility. In vitro analysis showed that BVS protects endothelial cells with magnesium hydroxide and selectively inhibits smooth muscle cell proliferation via everolimus treatment. The functional BVS was inserted into porcine coronary arteries for 28 days, and the results demonstrated that the restenosis and inflammation greatly decreased and re-endothelialization was enhanced as compared to others. CONCLUSIONS: This study provides new insights into the design of drug-incorporated BVS stent for coronary artery disease.
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OBJECTIVE: Putaminal iron deposition is an important feature that helps differentiate multiple system atrophy with predominant parkinsonism (MSA-p) from Parkinson's disease (PD). Most previous studies used visual inspection or quantitative methods with manual manipulation to perform this differentiation. We investigated the value of a new semiautomated diagnostic algorithm using 3T-MR susceptibility-weighted imaging for MSA-p. METHODS: This study included 26 MSA-p, 68 PD, and 41 normal control (NC) subjects. The algorithm was developed in 2 steps: 1) determine the image containing the remarkable putaminal margin and 2) calculate the phase-shift values, which reflect the iron concentration. The next step was to identify the best differentiating conditions among several combinations. The highest phaseshift value of each subject was used to assess the most effective diagnostic set. RESULTS: The raw phase-shift values were present along the lateral margin of the putamen in each group. It demonstrates an anterior- to-posterior gradient that was identified most frequently in MSA-p. The average of anterior 5 phase shift values were used for normalization. The highest area under the receiver operating characteristic curve (0.874, 80.8% sensitivity, and 86.7% specificity) of MSA-p versus PD was obtained under the combination of 3 or 4 vertical pixels and one dominant side when the normalization methods were applied. In the subanalysis for the MSA-p patients with a longer disease duration, the performance of the algorithm improved. CONCLUSION: This algorithm detected the putaminal lateral margin well, provided insight into the iron distribution of the putaminal rim of MSA-p, and demonstrated good performance in differentiating MSA-p from PD.
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Purpose: Recent studies have revealed that the expression of cancer-associated fibroblast (CAF) activation biomarkers in cancer cells is associated with clinical outcomes in patients with certain types of malignant tumors. However, whether the expression of CAF activation biomarkers affects the prognosis of colorectal cancer (CRC) has not been fully elucidated. This study aimed to evaluate the association between the expression of CAF activation biomarkers in cancer cells with cancer invasion and long-term oncological outcomes in patients with CRC. Methods: Cancer specimens obtained from 135 patients with stage I-III CRC were examined using immunohistochemical staining to evaluate the expression of fibroblast specific protein-1 (FSP-1), fibroblast activation protein α (FAPα), α-smooth muscle actin (α-SMA), and vimentin in cancer cells. Results: FSP-1 expression in cancer cells was significantly associated with lymphatic invasion, perineural invasion, tumor (T) status, and lymph node (N) status. FAPα expression in cancer cells was significantly associated with lymphatic invasion. On univariate and multivariate analyses, FSP-1 and α-SMA expression in cancer cells were associated with a short 10-year overall survival (OS) and high 10-year systemic recurrence (SR), respectively. Tumor budding was associated with a short 10-year OS. However, FAPα and vimentin did not contribute to the prognosis in this study. Conclusion: In this study, we found that FSP-1 expression in cancer cells was related to cancer invasion. Additionally, FSP-1 and α-SMA expression in cancer cells was associated with 10-year OS and SR, respectively. Therefore, these markers may be used as predictors of long-term oncological outcomes in patients with CRC.
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Background: Titanium is commonly used in blood-exposed medical devices because it has superior blood compatibility. Mycophenolic acid inhibits the proliferation of vascular smooth muscle cells. This study examined the effect of a non-polymer TiO2 thin film-coated stent with mycophenolic acid in a porcine coronary overstretch restenosis model. Methods: Thirty coronary arteries in 15 pigs were randomized into three groups in which the coronary arteries were treated with a TiO2 film-coated stent with mycophenolic acid (NTM, n = 10), everolimus-eluting stent with biodegradable polymer (EES, n = 10), or TiO2 film-coated stent (NT, n = 10). A histopathologic analysis was performed 28 days after the stenting. Results: There were no significant intergroup differences in injury score, internal elastic lamina area, or inflammation score. Percent area stenosis was significantly smaller in the NTM and EES groups than in the NT group (36.1 ± 13.63% vs. 31.6 ± 7.74% vs. 45.5 ± 18.96%, respectively, p = 0.0003). Fibrin score was greater in the EES group than in the NTM and NT groups [2.0 (range, 2.0-2.0) vs. 1.0 (range, 1.0-1.75) vs. 1.0 (range, 1.0-1.0), respectively, p < 0.0001]. The in-stent occlusion rate measured by micro-computed tomography demonstrated similar percent area stenosis rates on histology analysis (36.1 ± 15.10% in NTM vs. 31.6 ± 8.89% in EES vs. 45.5 ± 17.26% in NT, p < 0.05). Conclusion: The NTM more effectively reduced neointima proliferation than the NT. Moreover, the inhibitory effect of NTM on smooth muscle cell proliferation was not inferior to that of the polymer-based EES with lower fibrin deposition in this porcine coronary restenosis model.
ABSTRACT
Pigs are important experimental animals for cardiovascular research. Few porcine coronary atherosclerosis models have been developed; however, their induction requires more than six months. We developed a porcine coronary artery atherosclerosis model using nicotine injection with a balloon overdilation. A coronary balloon was placed in the porcine coronary artery and overdilated to induce a mechanical injury. Nicotine was administrated via intramuscular injection every day, and changes in the coronary artery were observed after four weeks. Coronary angiography revealed nicotine injection with a balloon overdilation group showed narrowing of the coronary artery at the injury site. The combination of balloon and nicotine significantly increased the intimal hyperplasia in optical coherence tomography analysis. Proliferated tunica media were noted in the nicotine injection with balloon overdilation groups and lack of collagen was observed in the tunica media at eight weeks. Quantitative analysis showed increased smooth muscle actin alpha (SMA), cluster of differentiation 68 (CD68), and Krüppel-like factor 4 (KLF4) in the nicotine injection with balloon overdilation groups. Immunohistochemistry results showed CD68-positive cells displayed SMA- and KLF4-positive reactivity in the border zone of the intimal hyperplasia. Our results show that nicotine injection with balloon overdilation can induce atherosclerotic lesions within one month, which can serve as an alternative pig animal model for the development of coronary stents.
Subject(s)
Atherosclerosis/pathology , Coronary Vessels/pathology , Nicotine/adverse effects , Angioplasty, Balloon , Animals , Atherosclerosis/etiology , Disease Models, Animal , Male , Swine , Tunica Intima/pathologyABSTRACT
The recently identified molecule P7C3 has been highlighted in the field of pain research. We examined the effect of intrathecal P7C3 in tissue injury pain evoked by formalin injection and determined the role of the GABA system in the activity of P7C3 at the spinal level. Male Sprague-Dawley rats with intrathecal catheters implanted for experimental drug delivery were studied. The effects of intrathecal P7C3 and nicotinamide phosphoribosyltransferase (NAMPT) administered 10 min before the formalin injection were examined. Animals were pretreated with bicuculline, a GABA-A receptor antagonist; saclofen, a GABA-B receptor antagonist; L-allylglycine, a glutamic acid decarboxylase (GAD) blocker; and CHS 828, an NAMPT inhibitor; to observe involvement in the effects of P7C3. The effects of P7C3 alone and the mixture of P7C3 with GABA receptor antagonists on KCl-induced calcium transients were examined in rat dorsal root ganglion (DRG) neurons. The expression of GAD and the concentration of GABA in the spinal cord were evaluated. Intrathecal P7C3 and NAMPT produced an antinociceptive effect in the formalin test. Intrathecal bicuculline, saclofen, L-allylglycine, and CHS 828 reversed the antinociception of P7C3 in both phases. P7C3 decreased the KCl-induced calcium transients in DRG neurons. Both bicuculline and saclofen reversed the blocking effect of P7C3. The levels of GAD expression and GABA concentration decreased after formalin injection and were increased by P7C3. These results suggest that P7C3 increases GAD activity and then increases the GABA concentration in the spinal cord, which in turn may act on GABA receptors causing the antinociceptive effect against pain evoked by formalin injection.
Subject(s)
Analgesics/administration & dosage , Carbazoles/administration & dosage , Nociceptive Pain/drug therapy , Pain Threshold/drug effects , Spinal Cord/drug effects , gamma-Aminobutyric Acid/metabolism , Animals , Calcium Signaling , Disease Models, Animal , Formaldehyde , Glutamate Decarboxylase/metabolism , Inflammation/chemically induced , Injections, Spinal , Male , Nociceptive Pain/etiology , Nociceptive Pain/metabolism , Nociceptive Pain/physiopathology , Rats, Sprague-Dawley , Spinal Cord/metabolism , Spinal Cord/physiopathologyABSTRACT
Cushing syndrome (CS) is rare in pregnancy, and few cases have been reported to date. Women with untreated CS rarely become pregnant because of the ovulatory dysfunction induced by hypercortisolism. It is difficult to diagnose CS in pregnancy because of its very low incidence, the overlap between the clinical signs of hypercortisolism and the physiological changes that occur during pregnancy and the changes in hypothalamus-pituitary-adrenal axis activity that occur during pregnancy and limit the value of standard diagnostic testing. However, CS in pregnancy is associated with poor maternal and fetal outcomes; therefore, its early diagnosis and treatment are important. Here, we report two patients with CS that was not diagnosed during pregnancy, in whom maternal and fetal morbidity developed because of hypercortisolism.
ABSTRACT
BACKGROUND: In clinical practice, one of the most important issues regarding the use of botulinum neurotoxin A (BoNT-A) is the proper storage conditions and the change in potency and quality over time after reconstitution. OBJECTIVE: This study aimed to investigate the change in potency and quality of reconstituted prabotulinumtoxin A (PraBoNT-A) over time when stored at different storage temperatures. MATERIALS AND METHODS: ICR/CD-1 mice and PraBoNT-A were used for the mouse intraperitoneal lethal dose 50% (LD50) test. A thorough quality evaluation of the product was performed. RESULTS: All of the reconstituted PraBoNT-A stored at different temperatures met the evaluation criteria for the suggested limits of estimated potency and for the quality assessment at every evaluated time point. When the stability of reconstituted PraBoNT-A was evaluated by regression analysis, the shelf life of reconstituted PraBoNT-A was found to be 99.24, 73.80, and 16.34 weeks in the case of PraBoNT-A stored at freezing, refrigeration, or room temperatures, respectively. CONCLUSION: Based on the results, the authors conclude that the efficacy and quality of the reconstituted PraBoNT-A product are not compromised at least for a certain period of time and that the shelf life of reconstituted PraBoNT-A is longest when stored at the freezing temperature.
Subject(s)
Botulinum Toxins, Type A/pharmacology , Animals , Cosmetic Techniques , Drug Storage/methods , Female , Freezing/adverse effects , Hot Temperature/adverse effects , Injections, Intraperitoneal , Lethal Dose 50 , Mice , Models, Animal , Refrigeration , Time FactorsABSTRACT
OBJECTIVES: The aim of this study was to evaluate temporal changes in coronary hemodynamic and physiological indexes in the non-infarct-related artery (IRA), which might be affected by adjacent infarcted myocardium, using an experimental animal model of acute myocardial infarction. BACKGROUND: There has been debate on the reliability of fractional flow reserve and resting pressure-derived indexes, including instantaneous wave-free ratio, in the non-IRA in patients with acute ST-segment elevation myocardial infarction. METHODS: In Yorkshire swine, acute myocardial infarction was simulated with selective balloon occlusion at the left circumflex coronary artery as the IRA for 30 min. Non-IRA stenosis was created using bare-metal stent implantation in the left anterior descending coronary artery 4 weeks before the experiments. Serial changes in systemic hemodynamic status, coronary pressure, and Doppler-derived coronary flow velocity were measured in a nonoccluded left anterior descending coronary artery as the non-IRA from baseline, balloon occlusion of the left circumflex coronary artery, and 15 min after reperfusion of the left circumflex coronary artery. RESULTS: Among the 6 experimental subjects, the median diameter stenosis of the non-IRA was 33.9% (interquartile range: 21.7% to 46.1%). During balloon occlusion of the IRA, there were transient significant changes in both resting and hyperemic aortic pressure, distal coronary pressure, averaged peak velocity, transstenotic pressure gradient, and microvascular resistance of the non-IRA (p < 0.020 for all). After reperfusion of the IRA, the resting averaged peak velocity (p = 0.002) and resting transstenotic pressure gradient (p = 0.004) were significantly increased and resting microvascular resistance (p = 0.004) was significantly decreased compared with their values in the baseline phase. However, the hyperemic averaged peak velocity (p = 0.479), hyperemic transstenotic pressure gradient (p = 0.778), and hyperemic microvascular resistance (p = 0.816) were not significantly different compared with those in the baseline phase. After reperfusion, fractional flow reserve in the non-IRA was not significantly different (0.94 ± 0.01 vs. 0.93 ± 0.01; p = 0.353), while coronary flow reserve (1.93 ± 0.07 vs. 1.36 ± 0.07; p = 0.025) and instantaneous wave-free ratio (0.97 ± 0.01 vs. 0.93 ± 0.01; p = 0.001) were significantly lower than baseline values. CONCLUSIONS: In a porcine model of acute myocardial infarction, occlusion of the IRA induced significant changes in systemic hemodynamic status and coronary circulatory indexes of the non-IRA. However, after reperfusion of the IRA, fractional flow reserve did not change significantly, whereas coronary flow reserve and instantaneous wave-free ratio showed significant changes compared with baseline values.
Subject(s)
Coronary Circulation , Coronary Stenosis/physiopathology , Coronary Vessels/physiopathology , Hemodynamics , Myocardial Infarction/physiopathology , Animals , Blood Flow Velocity , Blood Pressure , Cardiac Catheterization , Coronary Stenosis/diagnosis , Disease Models, Animal , Hyperemia/physiopathology , Male , Myocardial Infarction/diagnosis , Sus scrofa , Time Factors , Vascular ResistanceABSTRACT
BACKGROUND AND OBJECTIVES: Antiarrhythmic effect of renal denervation (RDN) after acute myocardial infarction (AMI) remains unclear. The goal of this study was to evaluate the effect of RDN on ventricular arrhythmia (VA) after AMI in a porcine model. METHODS: Twenty pigs were randomly divided into 2 groups based on RDN (RDN, n=10; Sham, n=10). After implanting a loop recorder, AMI was induced by occlusion of the middle left anterior descending coronary artery. Catheter-based RDN was performed for each renal artery immediately after creating AMI. Sham procedure used the same method, but a radiofrequency current was not delivered. Electrocardiography was monitored for 1 hour to observe VA. One week later, the animals were euthanized and the loop recorder data were analyzed. RESULTS: Ventricular fibrillation event rate and the interval from AMI creation to first VA in acute phase were not different between the 2 groups. However, the incidence of premature ventricular complex (PVC) was lower in the RDN than in the Sham. Additionally, RDN inhibited prolongation of the corrected QT (QTc) interval after AMI. The frequency of non-sustained or sustained ventricular tachycardia, arrhythmic death was lower in the RDN group in the early period. CONCLUSIONS: RDN reduced the incidence of PVC, inhibited prolongation of the QTc interval, and reduced VA in the early period following an AMI. These results suggest that RDN might be a therapeutic option in patients with electrical instability after AMI.
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The aim of this study was to evaluate the effects of fimasartan/amlodipine fixed-dosed combination (F/A) on left ventricle (LV) systolic function and infarct size in the rat myocardial infarction (MI) model. We induced MI in 20 rats by ligation of the left anterior descending coronary artery and they were divided into two groups [MI group (n=10) vs. MI+F/A 10 mg/kg group (n=10)]. F/A was administered for 28 days between day-7 and day-35 in the MI+F/A group and echocardiography was performed at day-7 and at day-35 after the induction of MI. Picrosirius red staining was performed to confirm the fibrotic tissue and infarct size was measured using image analysis program for Image J. At the 35-day follow-up, the LV ejection fraction (EF) was significantly higher (38.10±3.92% vs. 29.86±4.56%, p<0.001) and delta (day-35 minus day-7) EF was significantly higher (0.14±2.66% vs. -8.53±2.66%. p<0.001) in the MI+F/A group than the MI group. Systolic blood pressure was significantly lower in the MI+F/A group than the MI group (103.23±13.35 mmHg vs. 123.43±14.82 mmHg, p<0.01). The MI+F/A group had a smaller infarct size (26.84±5.31% vs. 36.79±3.10%, p<0.01) than the MI group at the 35-day follow-up. Oral administration of F/A 10 mg/kg could improve LV systolic function and reduce infarct size in a rat MI model.
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We evaluated the efficacy of fimasartan on perfusion defects and infarction size in an animal model of myocardial infarction (MI), with echocardiography and positron emission tomography (PET) using a 18F-labeled phosphonium cation (5-[18F]-fluoropentyl-triphenylphosphonium salt, [18F]FPTP) as a mitochondrial voltage sensor for myocardial imaging. We induced MI in 33 rats by ligation of the left coronary artery, and checked their cardiac PET image using [18F]FPTP for evaluation of myocardial perfusion. Rats were grouped into 3 groups according to their administered drugs: no drug (n=11), fimasartan 3 mg/kg (n=10), and fimasartan 10 mg/kg (n=12). Each designated drug was administered for 4 weeks, and follow-up PET and histologic examinations were done. In the PET analysis, a perfusion defect size was markedly improved in fimasartan 10 mg/kg group (35.9±7.0% to 28.4±6.9%, p<0.001), whereas treatment with fimasartan 3 mg/kg induced only an insignificant reduction of perfusion defect size (35.9±7.9% to 33.9±7.3%, p=0.095). Using 2, 3, 5-triphenyltetrazolium chloride staining, infarction size was the largest in the control group (36.5±8.3%), and was insignificantly lower in the fimasartan 3 mg/kg group (31.5±6.5%, p for the difference between the control group=0.146) and was significantly lower in the fimasartan 10 mg/kg group (26.3±7.6%, p for the difference between the control group=0.011). PET imaging using a 18F-labeled mitochondrial voltage sensor, [18F]FPTP, is useful in evaluation and monitoring of myocardial perfusion states, and treatment with fimasartan decreases the infarction size in animal MI model.
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BACKGROUND: Patients with acute myocardial infarction (AMI) have worse clinical outcomes than those with stable coronary artery disease despite revascularization. Non-culprit lesions of AMI also involve more adverse cardiovascular events. This study aimed to investigate the influence of AMI on endothelial function, neointimal progression, and inflammation in target and non-target vessels. METHODS: In castrated male pigs, AMI was induced by balloon occlusion and reperfusion into the left anterior descending artery (LAD). Everolimus-eluting stents (EES) were implanted in the LAD and left circumflex (LCX) artery 2 days after AMI induction. In the control group, EES were implanted in the LAD and LCX in a similar fashion without AMI induction. Endothelial function was assessed using acetylcholine infusion before enrollment, after the AMI or sham operation, and at 1 month follow-up. A histological examination was conducted 1 month after stenting. RESULTS: A total of 10 pigs implanted with 20 EES in the LAD and LCX were included. Significant paradoxical vasoconstriction was assessed after acetylcholine challenge in the AMI group compared with the control group. In the histologic analysis, the AMI group showed a larger neointimal area and larger area of stenosis than the control group after EES implantation. Peri-strut inflammation and fibrin formation were significant in the AMI group without differences in injury score. The non-target vessel of the AMI also showed similar findings to the target vessel compared with the control group. CONCLUSION: In the pig model, AMI events induced endothelial dysfunction, inflammation, and neointimal progression in the target and non-target vessels.
Subject(s)
Endothelium/physiology , Immunosuppressive Agents/therapeutic use , Inflammation/pathology , Myocardial Infarction/drug therapy , Neointima/pathology , Acute Disease , Animals , Arteries/pathology , Blood Cell Count , Disease Models, Animal , Drug-Eluting Stents , Everolimus/chemistry , Everolimus/therapeutic use , Immunosuppressive Agents/chemistry , Myocardial Infarction/pathology , Myocardium/pathology , Swine , Treatment OutcomeABSTRACT
15-hydroxyprostaglandin dehydrogenase (15-PGDH), the rate-limiting enzyme in prostaglandin E2 degradation, is decreased in gastric cancers and microRNA (miR)-21 is one of the regulators. We investigated the expression and regulation of 15-PGDH in eary gastric carcinogenesis utilizing endoscopic submucosal dissection (ESD) and gastric cancer cell lines. Expression of 15-PGDH and cyclooxygenase-2 as well as the promoter methylation of 15-PGDH were evaluted. CRISPR, miR-21 transfection, proliferation and apoptosis assays were also done. We observed significant decreases in 15-PGDH expression but no promoter methylation was detected in any ESDs. 15-PGDH suppression by CRISPR induced enhanced growth kinetics. miR-21, which was detected in high level in gastric tumors from the TGCA data, caused increased proliferation, decreased apoptosis. miR-21 overexpression was confirmed with CISH and RT-PCR in the ESDs. Loss of 15-PGDH occurs at the very early stage of gastric adenocarcinoma by miR-21. H. pylori infection may affect miR-21 up regulation. Maintaining 15-PGDH enzyme activity could be a new strategic measure in preventing gastric cancer especially tubular adenocarcinoma.
Subject(s)
Adenocarcinoma/genetics , Hydroxyprostaglandin Dehydrogenases/genetics , MicroRNAs/genetics , Stomach Neoplasms/genetics , Apoptosis/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Cyclooxygenase 2/genetics , Dinoprostone/genetics , Gene Expression Regulation, Enzymologic/genetics , Gene Expression Regulation, Neoplastic , Helicobacter Infections/genetics , Humans , Methylation , Promoter Regions, Genetic/genetics , Prospective Studies , Retrospective Studies , Transfection/methodsABSTRACT
We evaluated the effects of Ivabradine on left ventricle (LV) ejection fraction (EF) and LV infarcted tissue in the rat myocardial ischemia-reperfusion model. Twenty rats were randomly assigned to group 1 (ischemia-reperfusion, no treatment, n=10) and group 2 (ischemia-reperfusion + Ivabradine 10 mg/kg, n=10). Ivabradine was administered for 28 days. Echocardiography was performed at 7 days and at 28 days after the induction of ischemia-reperfusion injury. Cardiac fibrosis induced by ischemia-reperfusion injury was evaluated by Masson's trichrome staining. The infarct size was quantified using the Image J program. At the 28-day follow-up, LVEF was significantly higher (36.02±6.16% vs. 45.72±2.62%, p<0.001) and fractional shortening was significantly higher (15.23±2.84% vs. 20.13±1.38%, p<0.001) in group 2 than group 1. Delta (28 day minus 7 day) EF was significantly higher in group 2 than group 1 (-4.36±3.49% vs. 4.31±5.63%, p<0.001). Also, heart rate (beats/min) was significantly lower in group 2 than group 1 (251.67±25.19 vs. 199.29±31.33, p=0.025). Group 2 had a smaller infarct size (40.70±8.94% vs. 30.19±5.89%, p<0.01) than group 1 at 28-day follow-up. Oral administration of Ivabradine could improve LV systolic function and reduce infarcted tissue area in rat myocardial ischemia-reperfusion model.
ABSTRACT
Atherosclerotic plaques within the vasculature may eventually lead to heart failure. Currently, cardiac stenting is the most effective and least invasive approach to treat this disease. However, in-stent restenosis is a complex chronic side effect of stenting treatment. This study used coronary stents coated with stem cells secreting angiogenic growth factors via an inducible genome-editing system to reduce stent restenosis and induce re-endothelialization within the artery. The characteristics of the cells and their adhesion properties on the stents were confirmed, and the stents were transplanted into a swine model to evaluate restenosis and the potential therapeutic use of stents with stem cells. Restenosis was evaluated using optical coherence tomography (OCT), microcomputed tomography (mCT) and angiography, and re-endothelialization was evaluated by immunostaining after cardiac stent treatment. Compared to a bare metal stent (BMS) or a parental umbilical cord blood-derived mesenchymal stem cell (UCB-MSC)-coated stent, the stents with stem cells capable of the controlled release of hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) successfully reduced restenosis within the stent and induced natural re-endothelialization. Furthermore, UCB-MSCs exhibited the ability to differentiate into endothelial cells in Matrigel, and HGF and VEGF improved this differentiation. Our study indicates that stents coated with UCB-MSCs secreting VEGF/HGF reduce the restenosis side effects of cardiac stenting with improved re-endothelialization.
Subject(s)
Coronary Restenosis/therapy , Endothelium, Vascular/pathology , Fetal Blood/cytology , Hepatocyte Growth Factor/pharmacology , Mesenchymal Stem Cells/cytology , Stents , Vascular Endothelial Growth Factor A/pharmacology , Animals , Biomarkers/metabolism , Carcinogenesis/drug effects , Carcinogenesis/metabolism , Carcinogenesis/pathology , Cell Proliferation/drug effects , Coronary Restenosis/pathology , Coronary Vessels/drug effects , Coronary Vessels/pathology , Disease Models, Animal , Endothelium, Vascular/drug effects , Humans , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/metabolism , Mice, Inbred BALB C , Mice, Nude , Neovascularization, Physiologic/drug effects , SwineABSTRACT
Owing to the recent progress in regenerative medicine technology, clinical trials that harnessed the regeneration and immune modulation potentiality of stem cells for treating IBD have shown promising results. We investigated the feasibility and utility of intraluminal endoscopic transplantation of rat MSC sheets in murine models of experimental colitis for targeted delivery of stem cells to lesions. We isolated adipose-derived mesenchymal stem cells (AD-MSC) and bone marrow-derived mesenchymal stem cells (BM-MSC) from EGFP-transgenic rats and fabricated the cells in sheet forms using temperature-responsive culture dishes. The MSC sheets were endoscopically transplanted to the inflamed area in electrocoagulation and DNBS colitis model. The effect of the transplantation was verified using endoscopic scoring and histological analysis. In the electrocoagulation model, the AD-MSC group showed significantly decreased ulcer size in the transplanted regions. In the DNBS colitis model, the AD-MSC group showed decreased inflammation and colitis in the transplanted regions. Histologic analysis showed that the MSC sheets had successfully attached to the inflamed mucosa in both the electrocoagulation and DNBS colitis model. Our results show that endoscopic transplantation of MSC sheets could be a new effective mode of stem cell therapy for IBD treatment.
Subject(s)
Colitis/therapy , Inflammation/therapy , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Animals , Colitis/chemically induced , Colitis/genetics , Colitis/pathology , Dinitrofluorobenzene/analogs & derivatives , Dinitrofluorobenzene/toxicity , Disease Models, Animal , Endoscopes , Green Fluorescent Proteins/genetics , Humans , Inflammation/chemically induced , Inflammation/genetics , Inflammation/pathology , Mice , Rats , Rats, Transgenic/geneticsABSTRACT
Sleep apnea-hypopnea event detection has been widely studied using various biosignals and algorithms. However, most minute-by-minute analysis techniques have difficulty detecting accurate event start/end positions. Furthermore, they require hand-engineered feature extraction and selection processes. In this paper, we propose a new approach for real-time apnea-hypopnea event detection using convolutional neural networks and a single-channel nasal pressure signal. From 179 polysomnographic recordings, 50 were used for training, 25 for validation, and 104 for testing. Nasal pressure signals were adaptively normalized, and then segmented by sliding a 10-s window at 1-s intervals. The convolutional neural networks were trained with the data, which consisted of class-balanced segments, and were then tested to evaluate their event detection performance. According to a segment-by-segment analysis, the proposed method exhibited performance results with a Cohen's kappa coefficient of 0.82, a sensitivity of 81.1%, a specificity of 98.5%, and an accuracy of 96.6%. In addition, the Pearson's correlation coefficient between estimated apnea-hypopnea index (AHI) and reference AHI was 0.99, and the average accuracy of sleep apnea and hypopnea syndrome (SAHS) diagnosis was 94.9% for AHI cutoff values of ≥5, 15, and 30 events/h. Our approach could potentially be used as a supportive method to reduce event detection time in sleep laboratories. In addition, it can be applied to screen SAHS severity before polysomnography.
Subject(s)
Neural Networks, Computer , Polysomnography , Signal Processing, Computer-Assisted , Sleep Apnea Syndromes , Sleep , Adult , Aged , Female , Humans , Male , Middle Aged , Respiratory Rate , Sleep Apnea Syndromes/diagnosis , Sleep Apnea Syndromes/physiopathologyABSTRACT
Inflammation and thrombosis are linked to the use of polymer-based drug-eluting stents (DES). The aim of this study was to develop a polymer-free everolimus (EVL)-eluting stent using nitrogen-doped titanium dioxide (N-TiO2) and verify its efficacy by in vitro and in vivo assessment in a porcine coronary model. Various analytical approaches such as scanning electron microscopy and atomic force microscopy, electron spectroscopy, Fourier transform infrared spectrometry and contact angle measurement were employed for the characterization. As a part of biocompatibility assessment, platelet adhesion and smooth muscle cell (SMC) proliferation were examined. Bare metal stent (BMS), N-TiO2 stent, everolimus-eluting N-TiO2 (N-TiO2-EVL) stent, and commercialized EVL-eluting stent (EES) were randomly placed in forty coronary arteries in twenty pigs. After four weeks of implantation, the stents were subjected to histological and quantitative analysis. The N-TiO2 film used in this study was well coated without any cracks or peeling. Surface hydrophilicity (88.8% of angle decrement) could be associated with the decrease in surface roughness post N-TiO2 deposition (37.0%). The platelet adhesion on the N-TiO2 surfaces was less than that on the BMS surface. The proliferation of SMC was suppressed in the N-TiO2-EVL group (30.2%) but not in the BMS group. In the animal study, the percent area restenosis was significantly decreased in the N-TiO2-EVL group compared to that in the BMS group. The results (BMS; 47.0⯱â¯11.00%, N-TiO2-EVL; 31.7⯱â¯10.50%, and EES; 29.1⯱â¯11.21%, nâ¯=â¯10, pâ¯<â¯0.05) were almost at par with those of the commercialized EVL-eluting stent. The introduction of N-TiO2 deposition during fabrication of polymer-free DES may be an efficient accessorial process for preventing in-stent restenosis and thrombosis.