BackgroundDuring myocardial ischemia/reperfusion (I/R), a large amount of reactive oxygen species (ROS) is produced. In particular, overproduction of hydrogen peroxide (H2O2) is considered to be a main cause of I/R‐mediated tissue damage. We generated novel H2O2‐responsive antioxidant polymer nanoparticles (PVAX and HPOX) that are able to target the site of ROS overproduction and attenuate the oxidative stress‐associated diseases. In this study, nanoparticles were examined for their therapeutic effect on myocardial I/R injury.Methods and ResultsThe therapeutic effect of nanoparticles during cardiac I/R was evaluated in mice. A single dose of PVAX (3 mg/kg) showed a significant improvement in both cardiac output and fraction shortening compared with poly(lactic‐coglycolic acid) (PLGA) particle, a non‐H2O2‐activatable nanoparticle. PVAX also significantly reduced the myocardial infarction/area compared with PLGA (48.7±4.2 vs 14.5±2.1). In addition, PVAX effectively reduced caspase‐3 activation and TUNEL‐positive cells compared with PLGA. Furthermore, PVAX significantly decreased TNF‐α and MCP‐1 mRNA levels. To explore the antioxidant effect of PVAX by scavenging ROS, dihydroethidium staining was used as an indicator of ROS generation. PVAX effectively suppressed the generation of ROS caused by I/R, whereas a number of dihydroethidium‐positive cells were observed in a group with PLGA I/R. In addition, PVAX significantly reduced the level of NADPH oxidase (NOX) 2 and 4 expression, which favors the reduction in ROS generation after I/R.ConclusionsTaken together, these results suggest that H2O2‐responsive antioxidant PVAX has tremendous potential as a therapeutic agent for myocardial I/R injury.
BACKGROUND: Soft tissue trauma is a type of acute traumatic ischemia. We investigated in this study whether the edema, inflammation and ischemia caused by the trauma could be affected positively by hyperbaric oxygen (HBO) and ozone therapy.
We generated a novel nanoparticle called PVAX, which has intrinsic antiapoptotic and anti-inflammatory properties. This nanoparticle was loaded with neuropeptide Y (NPY), an angiogenic neurohormone that plays a central role in angiogenesis. Subsequently, we investigated whether PVAX-NPY could act as a therapeutic agent and induce angiogenesis and vascular remodeling in a murine model of hind limb ischemia. Adult C57BL/J6 mice ( = 40) were assigned to treatment groups: control, ischemia PBS, ischemia PVAX, ischemia NPY, and Ischemia PVAX-NPY Ischemia was induced by ligation of the femoral artery in all groups except control and given relevant treatments (PBS, PVAX, NPY, and PVAX-NPY). Blood flow was quantified using laser Doppler imaging. On and posttreatment, mice were euthanized to harvest gastrocnemius muscle for immunohistochemistry and immunoblotting. Blood flow was significantly improved in the PVAX-NPY group after 14 days. Western blot showed an increase in angiogenic factors VEGF-R2 and PDGF-β ( = 0.0035 and = 0.031, respectively) and antiapoptotic marker Bcl-2 in the PVAX-NPY group compared with ischemia PBS group ( = 0.023). Proapoptotic marker Smad5 was significantly decreased in the PVAX-NPY group as compared with the ischemia PBS group ( = 0.028). Furthermore, Y receptors were visualized in endothelial cells of newly formed arteries in the PVAX-NPY group. In conclusion, we were able to show that PVAX-NPY can induce angiogenesis and arteriogenesis as well as improve functional blood flow in a murine model of hind limb ischemia. Our research project proposes a novel method for drug delivery. Our patented PVAX nanoparticle can detect areas of ischemia and oxidative stress. Although there have been studies about delivering angiogenic molecules to areas of ischemic injury, there are drawbacks of nonspecific delivery as well as short half-lives. Our study is unique because it can specifically deliver NPY to ischemic tissue and appears to extend the amount of time therapy is available, despite NPY's short half-life.
BACKGROUND:This study was designed to compare the effects of resuscitation with cold and warm fluid on survival time, rate and volume of hemorrhage, hemodynamics, hypothermia, coagulopathy, acid-base balance, hematocrit, lactate, and base deficit during uncontrolled hemorrhagic shock (HS) model in rats.
ıntroduction: Pancreas is a rare injured after blunt abdominal traumas. Because, It is a retroperitoneal and other organs in front of pancreas, usually absorb pancreatic trauma. Isolated pancreatic injury is rate of % 5-10 and can occur in sports traumas where close contact and profound impact can be made. Case report: A 23 years old man was admitted to emergency department with abdominal pain, nausea and vomiting. He had received a blow to the epigastric region of abdomen, during a handball match four hours ago. Vital signs were stable and in his physical examination no abdominal movements were present while breathing. Intestinal sounds were hyperactive and there was a rigid abdomen with rebound and tenderness in all four quadrants. In abdominal ultrasonography it was reported that there was no emergency sonografic pathology, except a rectus sheath hematoma. As the initial serum amylase level was 398 U/L and after two hours in second control was further elevated 503 U/L, a contrast enhanced (oral-intravenous) abdominal computed tomography was performed. There was a hematoma in the head of pancreas, circum uncinat process. The patient admitted to hospital with the diagnosis of isolated blunt pancreatic injury. result: In patients with sport traumas to abdominal region, isolated pancreatic injuries must be considered. Serial amylase level measurements can be helpful to diagnose this life threatening condition but for certain diagnosis, Computed tomography evaluation must be necessary. İzole pankreas yaralanması % 5-10 civarında olup, yakın temas gerektiren, şiddetli çarpışmaların yaşanabileceği spor yaralanmalarında, nadiren de olsa karşımıza çıkabilir. Olgu Sunumu: Hentbol maçındayken, epigastrik bölgesine darbe alan 23 yaşında erkek hasta, karın ağrısı, bulantı, kusma şikayetleriyle olayın 4. saatinde acil servisimize başvurdu. Hasta geldiğinde vital bulguları stabildi, fizik muayenesinde; inspeksiyonda batın solunuma katılmıyor, dinlemekle barsak sesleri hiperaktif, palpasyonda tüm kadranlarda hassasiyet, defans ve rebaund mevcuttu. Yapılan batın ultrasonunda; rektus abdominis kas hematomu haricinde, acil sonografik patoloji saptanmadı. Yapılan laboratuar tetkiklerinde; serum amilaz düzeyinin 398 U/L saptanması; iki saat sonra yapılan kontrollerde 503 U/L saptanarak, daha da yükselmesi sonucunda, hastada IV/oral kontrastlı batın tomografisi planlandı. Pankreas başında, uncinat processin etrafında hematom saptanan hasta, izole künt pankreas yaralanması tanısıyla hastaneye yatışı yapıldı. Sonuç: Abdominal bölgeye olan spor travmaları sonrası izole pankreas yaralanmaları olabileceği akılda tutulmalıdır. Bu hayatı tehtid eden durumun tanısında; seri yapılan serum amilaz ölçümleri faydalıdır, fakat kesin tanı için mutlaka bilgisayarlı tomografiyle evaluasyon gereklidir.
BackgroundSacroiliac provocation tests are used in cases with a suspected diagnosis of spondyloarthritis (SpA). However, all of the studies on the diagnostic value of these physical examination tests have been carried out in non-inflammatory sacroiliac (SI) joint pathologies, and the data about the contribution of these tests in the diagnosis of SpA is poor.ObjectivesTo investigate the role of sacroiliac provocation tests in the diagnosis of SpA, and their relation with inflammatory findings in magnetic resonance imaging (MRI).Methods51 patients (F/M=7/44) with chronic low back and/or hip pain admitted to the rheumatology clinic were included in the study. The history of patients participating in the study were taken by a rheumatologist, and another experienced rheumatologist who is unaware of the patient's medical information performed 5 different challenge tests for SI joints (sacroiliac compression test, sacroiliac distraction test, FABER-Patrick test, sacral thrust test, drop test) within a certain protocol. All patients were evaluated with sacroiliac MRI for the presence of acute inflammation. The sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio (LR) and diagnostic accuracy of each physical examination methods were calculated with taking clinical diagnosis and sacroiliac MRI as the standard evidence of acute inflammation (2 different comparisons).Results30 patients included in the study met the diagnostic criteria for SpA. Calculations related to diagnostic value of each examination method are summarized in Table 1.When data was analyzed for the diagnosis of SpA, the positive LR value of provocation tests ranged between 1.4–2.24.For the relationship between the examination findings and acute changes in SI joint MRI, LR values ranged positively between 1.1–2.79.Inflammatory back pain in history was associated with a positive LR value of 1.17 in predicting the diagnosis of SpA and a positive LR value of 1.37 in predicting acute changes in MRI.Table 1.The diagnostic features of sacroiliac joint provocation tests (acute inflammation in MRI are taken as standard)Sacroiliac compression testSacroiliac distraction testFABER-PatrickSacral thrust testDrop testDxMRIDxMRIDxMRIDxMRIDxMRIPrevalance0.410.410.650.650.610.350.760.760.430.43Sensitivity0.430.530.710.770.460.430.790.870.610.53Spesifity0.610.760.430.520.780.760.260.380.780.71PPV0.570.760.610.700.720.720.560.670.770.73NPV0.470.530.560.610.550.480.500.670.620.52LR+1.102.241.261.612.141.821.061.402.791.87LR-0.940.610.660.450.680.740.820.350.500.65Accuracy0.510.630.590.670.350.570.550.670.690.61Dx, diagnosis; PPV, Positive predictive value; NPV, negative predictive value; LR, likelihood ratio.ConclusionsThese results show that the contribution of SI provocation tests for predicting the findings of inflammation in MRI or SpA diagnosis is extremely limited.When compared to the diagnostic accuracy of similar tests in non-inflammatory conditions of SI joint in the literature, the predictive value of pr...
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