707 research outputs found
Motion characteristics of the vertebral segments with lumbar degenerative spondylolisthesis in elderly patients
Objective
Although some studies have reported on the kinematics of the lumbar segments with degenerative spondylolisthesis (DS), few data have been reported on the in vivo 6 degree-of-freedom kinematics of different anatomical structures of the diseased levels under physiological loading conditions. This research is to study the in vivo motion characteristics of the lumbar vertebral segments with L4 DS during weight-bearing activities.
Methods
Nine asymptomatic volunteers (mean age 54.4) and 9 patients with L4 DS (mean age 73.4) were included. Vertebral kinematics was obtained using a combined MRI/CT and dual fluoroscopic imaging technique. During functional postures (supine, standing upright, flexion, and extension), disc heights, vertebral motion patterns and instability were compared between the two groups.
Results
Although anterior disc heights were smaller in the DS group than in the normal group, the differences were only significant at standing upright. Posterior disc heights were significantly smaller in DS group than in the normal group under all postures. Different vertebral motion patterns were observed in the DS group, especially in the left–right and cranial–caudal directions during flexion and extension of the body. However, the range of motions of the both groups were much less than the reported criteria of lumbar spinal instability.
Conclusion
The study showed that lumbar vertebra with DS has disordered motion patterns. DS did not necessary result in vertebral instability. A restabilization process may have occurred and surgical treatment should be planned accordingly.China Scholarship CouncilNational Institutes of Health (U.S.) (R21AR057 989
Multiple Surgical Treatments for Recurrent Retroperitoneal Hemorrhage in a COVID-19 Patient with Respiratory Failure on Extracorporeal Membrane Oxygenation
Extracorporeal membrane oxygenation (ECMO) may be required in patients with corona virus disease-19 (COVID-19) and respiratory failure. Anticoagulation is the standard treatment to prevent complications of ECMO and COVID-19 coagulopathy, however, there is a risk of bleeding. Some patients with retroperitoneal hemorrhage (RPH) have been treated with angiography-embolization. We report on a patient with COVID-19 on ECMO who underwent multiple operations (×5) for recurrent RPH. A 46-year-old man was admitted with COVID-19 pneumonia. ECMO with anticoagulation therapy was initiated. The patient developed RPH, caused by external compression of the inferior vena cava interrupting the ECMO inflow, and surgical hematoma evacuation was performed, with no obvious bleeding focus during the multiple surgeries. Following the patient’s recovery, a follow-up computed tomography scan showed the hematoma had been resolved, but there was a dilemma regarding anticoagulation. Lowering the threshold for surgical treatment, enabled treatment of a patient with serious RPH
Outcomes of endovascular treatment for aortic pseudoaneurysm in Behcet's disease
ObjectiveTo evaluate the effectiveness of endovascular stent grafting for surgical management of aortic pseudoaneurysm in patients with Behcet's disease (BD).MethodsWe present a single-institution retrospective cohort of patients with aortic pseudoaneurysm and BD treated with aortic stent grafting. Computed tomography imaging was obtained preoperatively in all patients and once within 2 weeks postoperatively, and then annually. Clinical follow-up and erythrocyte sedimentation rate were used to follow BD activity. Immunosuppressant therapy was instituted prior to endovascular treatment unless a contraindication existed.ResultsFrom 1998 to 2012, 10 patients (eight male, two female; median age, 39) with BD and aortic pseudoaneurysm were treated with endovascular stent grafting at this institution. Ninety percent of these patients received immunosuppressive therapy before and after surgical treatment. The median follow-up period was 57 months (interquartile range, 43-72). The locations of the 12 pseudoaneurysms treated in this cohort were infrarenal abdominal aorta (seven), descending thoracic aorta (four), and aortic arch (one). Median pseudoaneurysm size was 4.5 cm (interquartile range, 3.4-5.9). At long-term follow-up, complete resolution of the aortic pseudoaneurysm was noted in all patients. No endoleaks occurred. Newly developed pseudoaneurysm at the distal margin of the stent graft was noted in one patient 17 months after the stent graft procedure. One patient required a subsequent stent graft placement for an expanding pseudoaneurysm of the subclavian artery. No patient deaths occurred during the follow-up period.ConclusionsEndovascular treatment of aortic pseudoaneurysm with stent-grafting in patients with BD is safe and effective with long-term durability
Prevalence and Management of Diabetes in Korean Adults: Korea National Health and Nutrition Examination Surveys 1998–2005
OBJECTIVE: This research investigated recent changes in the prevalence and management status of diabetes among Korean adults.
RESEARCH DESIGN AND METHODS: The Korea National Health and Nutrition Examination Survey (KNHANES), a nationwide survey examining the general health and nutrition status of the Korean people, was conducted in 1998, 2001, and 2005. Using the first (1998; n = 5,645), second (2001; n = 4,154), and third (2005; n = 4,628) KNHANES datasets, in the present study, we estimated the prevalence of diabetes among Korean adults (aged >or=30 years), the proportions of known cases of diabetes, and the proportions of well-controlled cases of diabetes, as defined by either the American Diabetes Association (A1C <7%) or the International Diabetes Federation guidelines (A1C <6.5%).
RESULTS: In 2005, the prevalence of diabetes was estimated to be 9.1% (approximately 2.58 million people: 10.2% of men and 7.9% of women), including 6.2% with known diabetes and 2.9% with newly diagnosed diabetes. The prevalence of impaired fasting glucose was 17.4% (approximately 4.94 million people). The proportion of known cases of diabetes drastically increased from 23.2% in 1998 to 41.2% in 2001 and 68.0% in 2005 (P < 0.0001). Among known diabetic patients in 2005, 43.5 and 22.9% had A1C levels <7.0 and <6.5%, respectively.
CONCLUSIONS: The overall prevalence of diabetes in Korea has not changed significantly between 1998 and 2005. Physician diagnosis and treatment rates of diabetes have significantly improved during this period, but glycemic control was still poorer than that in other developed countriesope
Prevention of hypoglycemia-induced neuronal death by minocycline
Diabetic patients who attempt strict management of blood glucose levels frequently experience hypoglycemia. Severe and prolonged hypoglycemia causes neuronal death and cognitive impairment. There is no effective tool for prevention of these unwanted clinical sequelae. Minocycline, a second-generation tetracycline derivative, has been recognized as an anti-inflammatory and neuroprotective agent in several animal models such as stroke and traumatic brain injury. In the present study, we tested whether minocycline also has protective effects on hypoglycemia-induced neuronal death and cognitive impairment. To test our hypothesis we used an animal model of insulin-induced acute hypoglycemia. Minocycline was injected intraperitoneally at 6 hours after hypoglycemia/glucose reperfusion and injected once per day for the following 1 week. Histological evaluation for neuronal death and microglial activation was performed from 1 day to 1 week after hypoglycemia. Cognitive evaluation was conducted 6 weeks after hypoglycemia. Microglial activation began to be evident in the hippocampal area at 1 day after hypoglycemia and persisted for 1 week. Minocycline injection significantly reduced hypoglycemia-induced microglial activation and myeloperoxidase (MPO) immunoreactivity. Neuronal death was significantly reduced by minocycline treatment when evaluated at 1 week after hypoglycemia. Hypoglycemia-induced cognitive impairment is also significantly prevented by the same minocycline regimen when subjects were evaluated at 6 weeks after hypoglycemia. Therefore, these results suggest that delayed treatment (6 hours post-insult) with minocycline protects against microglial activation, neuronal death and cognitive impairment caused by severe hypoglycemia. The present study suggests that minocycline has therapeutic potential to prevent hypoglycemia-induced brain injury in diabetic patients
An autoregulatory loop controlling orphan nuclear receptor DAX-1 gene expression by orphan nuclear receptor ERRγ
The estrogen receptor-related receptor gamma (ERRγ/ERR3/NR3B3) is a member of the nuclear receptor superfamily that activates transcription in the absence of ligand. However, the detailed mechanism of gene regulation by ERRγ is not fully understood. In this study we have found that the orphan nuclear receptor ERRγ activates the DAX-1 promoter, which, in turn, represses transactivation by ERRγ. Serial deletions of mouse DAX-1 (mDAX-1) gene promoter have revealed that the region responding to ERRγ is located between −129 and −121 bp and −334 and −326 bp. Gel shift assays and chromatin immunoprecipitation (ChIP) assays demonstrated that ERRγ binds directly to the mDAX-1 promoter. Site-directed mutagenesis results demonstrated that ERRE1 (−129 to −121 bp) is more important than ERRE2 (−334 to −326 bp) which is not conserved in the human DAX-1 promoter. In addition, adenovirus-mediated overexpression of ERRγ induced DAX-1 gene expression in MCF-7 breast cancer cells that co-expressed ERRγ and DAX-1. Moreover, yeast two-hybrid and glutathione S-transferase (GST)-pull down assays demonstrated that DAX-1 physically interacted with ERRγ and inhibited ERRγ transactivation, and that this interaction was dependent on the AF-2 domain of ERRγ. In addition, in vitro competition assays showed that DAX-1 inhibited PGC-1α mediated ERRγ transactivation, via competition between these two factors for the AF-2 binding domain. We thus propose a novel autoregulatory loop that controls DAX-1 gene expression by ERRγ
Mechanical Circulatory Support to Control Medically Intractable Arrhythmias in Pediatric Patients After Cardiac Surgery
Postoperative intractable arrhythmia can result in high morbidity and mortality. This report describes our experiences using mechanical circulatory support (MCS) to control medically intractable arrhythmias in three pediatric patients with congenital heart disease (CHD), after palliative or total corrective open-heart surgery
Critical heat flux enhancement in flow boiling of Al 2O 3 and SiC nanofluids under low pressure and low flow conditions
Critical heat flux (CHF) is the thermal limit of a phenomenon in which a phase change occurs during heating (such as bubbles forming on a metal surface used to heat water), which suddenly decreases the heat transfer efficiency, thus causing localized overheating of the heating surface. The enhancement of CHF can increase the safety margins and allow operation at higher heat fluxes; thus, it can increase the economy. A very interesting characteristic of nanofluids is their ability to significantly enhance the CHF. Nanofluids are nanotechnology-based colloidal dispersions engineered through the stable suspension of nanoparticles. All experiments were performed in round tubes with an inner diameter of 0.01041 m and a length of 0.5 m under low pressure and low flow (LPLF) conditions at a fixed inlet temperature using water, 0.01 vol.% Al2O3/water nanofluid, and SiC/water nanofluid. It was found that the CHF of the nanofluids was enhanced and the CHF of the SiC/water nanofluid was more enhanced than that of the Al2O3/water nanofluid.close6
Dual Roles of Quercetin in Platelets: Phosphoinositide-3-Kinase and MAP Kinases Inhibition, and cAMP-Dependent Vasodilator-Stimulated Phosphoprotein Stimulation
Background. Progressive diseases including cancer, metabolic, and cardiovascular disorders are marked by platelet activation and chronic inflammation. Studies suggest that dietary flavonoids such as quercetin possess antioxidant, anti-inflammatory, and antiplatelet properties, which could prevent various chronic diseases including atherosclerosis and thrombosis. However, the mechanism and the signaling pathway that links quercetin's antiplatelet activity with its anti-inflammatory property is limited and thus further exploration is required. The aim of this paper was to examine the link between antiplatelet and anti-inflammatory roles of quercetin in agonist-induced platelet activation. Methods. Quercetin effects on agonist-activated platelet-aggregation, granule-secretion, [Ca2+]i, and glycoprotein-IIb/IIIa activation were examined. Its effects on PI3K/Akt, VASP, and MAPK phosphorylations were also studied on collaged-activated platelets. Results. Quercetin dose dependently suppressed collagen, thrombin, or ADP-induced platelet aggregation. It significantly inhibited collagen-induced ATP release, P-selectin expression, [Ca2+]i mobilization, integrin-αIIbβ3 activation, and augmented cAMP and VASP levels. Moreover, quercetin attenuated PI3K, Akt, ERK2, JNK1, and p38 MAPK activations, which were supported by platelet-aggregation inhibition with the respective kinase inhibitors. Conclusion. Quercetin-mediated antiplatelet activity involves PI3K/Akt inactivation, cAMP elevation, and VASP stimulation that, in turn, suppresses MAPK phosphorylations. This result suggests quercetin may have a potential to treat cardiovascular diseases involving aberrant platelet activation and inflammation
- …