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1.
Vascular ; : 17085381241257742, 2024 Jun 11.
Article En | MEDLINE | ID: mdl-38861481

OBJECTIVES: Abdominal Aortic Aneurysms (AAA) in females are less prevalent, have higher expansion rates and experience rupture at smaller diameters than in males. Studies have compared outcomes of the retroperitoneal (RP) and transperitoneal (TP) approach in open aortic aneurysm repair (OAR) with conflicting results. No study to date has compared the two approaches solely in females. In this study we compare midterm outcomes of the RP and TP approach in females undergoing OAR. METHODS: Single-center, retrospective review of all females undergoing OAR from 2010 to 2021. Patients undergoing elective, symptomatic and ruptured OAR were included. The cohort was stratified by surgical approach RP versus TP and midterm outcomes were compared amongst the groups. Outcomes included mortality, graft related, and non-graft related complications. RESULTS: A total of 244 patients (RP n = 133; TP n = 111) were identified. Follow-up period was 28 ± 30.7 months. Baseline perioperative characteristics were similar except that more people in the RP group had ejection fraction ((EF) > 50% (82% vs 68%), p = .037). Patients who underwent RP repair had longer visceral/renal ischemia time (p = .01), larger graft diameter (18 vs 16 mm; p = <0.001), were more likely to have a suprarenal clamp placed(70.5 vs 48.2; p < .001), and had decreased autotransfusion volume (611 vs 861 mL; p < .01) compared to those who underwent TP repair. Number of deaths was higher in the TP group during study follow-up period (36.4 vs 23.8; p = .035), but the difference of the time to event analysis was not significant. There was no difference in all-cause survival at 36 months between RP and TP (77.8 vs 76.8; p = .045). Overall midterm complications were 9.5% in both groups. Any graft related complication was 1.8% in TP versus 3% RP (p = .69). In a multivariable model, after adjusting for age, urgency, smoking, prior aneurysm repair, and ASA level, the hazard ratio decreases with the RP approach, however this did not reach significance (p = .052). CONCLUSION: In a 12-year period of OAR in females, TP and RP results were comparable at midterm analysis. The RP approach appeared to be used more often for OAR requiring suprarenal clamping. Although the TP group had increased mortality, the difference of the time to event analysis was not significant. Midterm postoperative complications in both groups were low. This suggests that both approaches are safe in the female population and decision should be driven by anatomy and surgeon's preference.

2.
Int J Biol Macromol ; 257(Pt 1): 128558, 2024 Feb.
Article En | MEDLINE | ID: mdl-38048927

Reperfusion therapy is the most effective treatment for acute myocardial infarction. However, reperfusion itself can also cause cardiomyocytes damage. Pyroptosis has been shown to be an important mode of myocardial cell death during ischemia-reperfusion. Non-coding RNAs (ncRNAs) play critical roles in regulating pyroptosis. The regulation of pyroptosis by microRNAs, long ncRNAs, and circular RNAs may represent a new mechanism of myocardial ischemia-reperfusion injury. This review summarizes the currently known regulatory roles of ncRNAs in myocardial ischemia-reperfusion injury and interactions between ncRNAs. Potential therapeutic strategies using ncRNA modulation are also discussed.


MicroRNAs , Myocardial Infarction , Myocardial Reperfusion Injury , Humans , Myocardial Reperfusion Injury/genetics , Myocardial Reperfusion Injury/metabolism , Pyroptosis/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Untranslated/genetics , Myocardial Infarction/genetics
3.
Ann Vasc Surg ; 98: 102-107, 2024 Jan.
Article En | MEDLINE | ID: mdl-37423328

BACKGROUND: Complex open abdominal aortic aneurysm (AAA) repair often necessitates revascularization of renal arteries by either renal artery reimplantation or bypass. This study aims to evaluate the perioperative and short term outcomes between these 2 strategies of renal artery revascularization. METHODS: We performed a retrospective review of patients who underwent open AAA repair from 2004 to 2020 at our own institution. Patients who underwent elective suprarenal, juxtarenal, or type 4 thoracoabdominal aneurysm repair were identified using current procedural terminology (CPT) codes and a retrospectively maintained database of AAA patients. Patients who had symptomatic aneurysm or significant renal artery stenosis before AAA repair were excluded. Patient demographics, intraoperative conditions, renal function, bypass patency, and perioperative and postoperative outcomes at 30 days and 1 year were compared. RESULTS: One hundred and forty-three patients underwent either renal artery reimplantation (n = 86) or bypass (n = 57) during this time period. The mean age was 69.7 years and 76.2% of the patients were male. Median preoperative creatinine was 1.2 mg/dL for the renal bypass group versus 1.06 mg/dL for reimplantation (P = 0.088). Both groups had similar median preoperative glomerular filtration rate (GFR) of >60 mL/min (P = 0.13). Bypass and reimplantation groups had similar perioperative complications including acute kidney injury (51.8% vs. 49.4% P = 0.78), inpatient dialysis (3.6% vs. 1.2% P = 0.56), myocardial infarction (1.8% vs. 2.4% P = 0.99), and death (3.5% vs. 4.7% P = 0.99), respectively. During the 30-day follow-up period, renal artery stenosis was identified in 9.8% of bypasses and 6.7% of reimplantations (P = 0.71). Six point one percent of patients in the bypass group had renal failure requiring dialysis (both acute and permanent) compared to 1.3% in reimplantation group (P = 0.3). For those who had 1-year follow-up, the reimplantation group had higher new incidence of renal artery stenosis compared to bypass group (6 vs. 0 P = 0.16). CONCLUSIONS: Given that there is no significant difference in outcomes between renal artery reimplantation and bypass within 30 days or at 1-year follow-up, both bypass and reimplantation are acceptable means for renal artery revascularization during elective AAA repair.


Acute Kidney Injury , Aortic Aneurysm, Abdominal , Blood Vessel Prosthesis Implantation , Renal Artery Obstruction , Humans , Male , Aged , Female , Renal Artery/diagnostic imaging , Renal Artery/surgery , Retrospective Studies , Treatment Outcome , Aortic Aneurysm, Abdominal/diagnostic imaging , Aortic Aneurysm, Abdominal/surgery , Aortic Aneurysm, Abdominal/complications , Acute Kidney Injury/diagnosis , Acute Kidney Injury/etiology , Replantation/adverse effects , Blood Vessel Prosthesis Implantation/adverse effects , Risk Factors , Postoperative Complications/etiology
4.
Eur J Pharmacol ; 956: 175985, 2023 Oct 05.
Article En | MEDLINE | ID: mdl-37572943

Ischemia-induced myocardial infarction is regarded as one of the major killers of humans worldwide. Kinsenoside (KD), a primary active ingredient derived from Anoectochilus roxburghii, shows antioxidant and vascular protective properties. Myocardial ischemia/reperfusion (I/R) injury is associated with oxidative damage and could be regulated by KD. However, its targets and the exact mechanism by which it operates remains unclear. The aim of this study was to investigate the role of KD in myocardial I/R injury and to define the mechanism by which it works. We established both myocardial I/R model in vivo and hypoxia/reoxygenation (H/R) cardiomyocyte model in vitro in this study. KD can attenuate I/R-induced myocardial injury in vivo and inhibit H/R-induced injury in vitro in a dose-dependent manner. KD increased mitochondrial membrane potential, SOD activity, and GSH activity in cardiomyocytes, whereas MDA accumulation, iron accumulation, and Mito-ROS production were decreased. We intersected differentially expressed genes (DEGs) from RNA-seq results with ferroptosis-related genes, and found KD significantly downregulated COX2 expression and upregulated GPX4 expression. These findings were further confirmed by Western blot analysis. Additionally, KD increased AKT phosphorylation and Nrf2 translocation into the nucleus, as well as HO-1 expression. When Akt or Nrf2 were inhibited in the KD group, the anti-ferroptosis properties of KD were nullified. Thus, Kinsenoside may exert anti-ferroptosis effect in myocardial I/R injury by decreasing mitochondrial dysfunction and increasing anti-oxidation through the Akt/Nrf2/HO-1 signaling pathway, suggesting it could be used as a potential therapeutic agent for myocardial reperfusion injury.


Coronary Artery Disease , Myocardial Infarction , Myocardial Reperfusion Injury , Humans , Myocardial Reperfusion Injury/drug therapy , Myocardial Reperfusion Injury/metabolism , Proto-Oncogene Proteins c-akt/metabolism , NF-E2-Related Factor 2/metabolism , Oxidative Stress , Myocardial Infarction/drug therapy , Myocardial Infarction/prevention & control
5.
J Vasc Surg ; 78(3): 633-637, 2023 09.
Article En | MEDLINE | ID: mdl-37182816

OBJECTIVE: Aneurysmal pathology of the aorta is well-defined in the Marfan syndrome (MFS) population. Owing in part to the rarity of pathologies, the prevalence of intracranial aneurysms (IA) in MFS is poorly defined. There is debate as to whether or not there is an association between the two. The aim of this study was to evaluate the prevalence of IA in a population of patients with MFS who underwent intracranial imaging. METHODS: This was a single-center retrospective review of patients with MFS. Between 1995 and 2021, 983 patients were reviewed. We identified 198 patients with MFS who had intracranial imaging. Imaging consisted of CTA and/or MRA, and was read by an attending radiologist. Details of the aneurysm, patient demographics, and aortic characteristics were collected. RESULTS: The prevalence of IA was 7.1% (14/198). Age of patients with IA (55.0 ± 15.1 years) was not significantly different than those without IA (52.6 ± 16.0 years) (P = .58). The most common location of IA was the internal carotid artery. The mean diameter of the IA was 7 ± 5.8 mm. No ruptures of the internal carotid artery were identified. One patient (0.5%) underwent intervention for the IA. There were no significant differences found in aortic characteristic including dimensions, history of dissection, or aneurysm. CONCLUSIONS: In a large, single-center experience over 20 years, we identified patients with confirmed MFS who underwent intracranial imaging. The prevalence of IA in our experience was 7.1%. There were no patient or aortic characteristics found to be significantly associated with IA; however, this finding may be due to the small number of aneurysms. Although this number is higher than the historically reported prevalence in the general population, a collection of experiences from multiple institutions will likely be required to truly define the risk of IA in MFS and to determine whether screening is warranted.


Intracranial Aneurysm , Marfan Syndrome , Humans , Adult , Middle Aged , Aged , Marfan Syndrome/complications , Marfan Syndrome/diagnosis , Marfan Syndrome/epidemiology , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/epidemiology , Intracranial Aneurysm/etiology , Prevalence , Aorta , Retrospective Studies
6.
Front Psychol ; 14: 1094488, 2023.
Article En | MEDLINE | ID: mdl-36814669

Objective: Based on the theoretical model for the "stress-sleep" relationship, this study investigated the impact of parental phubbing on adolescent sleep quality problems and a moderated mediation mechanism. Methods: A total of 781 adolescents was surveyed using the Chinese version of Parental Phubbing Scale, the Ultra-brief Screening Scale for Depression and Anxiety Scale, the Self-Control Questionnaire for Chinese children, and the Chinese version of Pittsburgh Sleep Quality Index Scale. Results: Parental phubbing and negative emotions were significantly and positively correlated to sleep quality problems, but self-control was not correlated to sleep quality problems. Parental phubbing directly influenced sleep quality problems and also indirectly influenced sleep quality problems through the mediating effect of negative emotions. Moreover, self-control played a moderating role in the path of parental phubbing affecting negative emotions. That is, the effect was more significant for adolescents low in self-control relative to those high in self-control. Conclusion: Parental phubbing is a risk factor for adolescent sleep quality problems. This study is the first to demonstrate empirical evidence for the relationship between parental phubbing and sleep quality problems.

7.
Biomimetics (Basel) ; 8(1)2023 Feb 15.
Article En | MEDLINE | ID: mdl-36810414

Many diseases, such as stroke, arthritis, and spinal cord injury, can cause severe hand impairment. Treatment options for these patients are limited by expensive hand rehabilitation devices and dull treatment procedures. In this study, we present an inexpensive soft robotic glove for hand rehabilitation in virtual reality (VR). Fifteen inertial measurement units are placed on the glove for finger motion tracking, and a motor-tendon actuation system is mounted onto the arm and exerts forces on fingertips via finger-anchoring points, providing force feedback to fingers so that the users can feel the force of a virtual object. A static threshold correction and complementary filter are used to calculate the finger attitude angles, hence computing the postures of five fingers simultaneously. Both static and dynamic tests are performed to validate the accuracy of the finger-motion-tracking algorithm. A field-oriented-control-based angular closed-loop torque control algorithm is adopted to control the force applied to the fingers. It is found that each motor can provide a maximum force of 3.14 N within the tested current limit. Finally, we present an application of the haptic glove in a Unity-based VR interface to provide the operator with haptic feedback while squeezing a soft virtual ball.

8.
IEEE Trans Neural Netw Learn Syst ; 34(4): 1742-1753, 2023 Apr.
Article En | MEDLINE | ID: mdl-33684047

Event cameras as bioinspired vision sensors have shown great advantages in high dynamic range and high temporal resolution in vision tasks. Asynchronous spikes from event cameras can be depicted using the marked spatiotemporal point processes (MSTPPs). However, how to measure the distance between asynchronous spikes in the MSTPPs still remains an open issue. To address this problem, we propose a general asynchronous spatiotemporal spike metric considering both spatiotemporal structural properties and polarity attributes for event cameras. Technically, the conditional probability density function is first introduced to describe the spatiotemporal distribution and polarity prior in the MSTPPs. Besides, a spatiotemporal Gaussian kernel is defined to capture the spatiotemporal structure, which transforms discrete spikes into the continuous function in a reproducing kernel Hilbert space (RKHS). Finally, the distance between asynchronous spikes can be quantified by the inner product in the RKHS. The experimental results demonstrate that the proposed approach outperforms the state-of-the-art methods and achieves significant improvement in computational efficiency. Especially, it is able to better depict the changes involving spatiotemporal structural properties and polarity attributes.

9.
IEEE Trans Pattern Anal Mach Intell ; 45(1): 1233-1249, 2023 01.
Article En | MEDLINE | ID: mdl-35085071

Neuromorphic vision sensor is a new bio-inspired imaging paradigm emerged in recent years. It uses the asynchronous spike signals instead of the traditional frame-based manner to achieve ultra-high speed sampling. Unlike the dynamic vision sensor (DVS) that perceives movement by imitating the retinal periphery, the spike camera was developed recently to perceive fine textures by simulating a small retinal region called the fovea. For this new type of neuromorphic camera, how to reconstruct ultra-high speed visual images from spike data becomes an important yet challenging issue in visual scene perception, analysis, and recognition applications. In this paper, a bio-inspired visual reconstruction framework for the spike camera is proposed for the first time. Its core idea is to use the biologically inspired adaptive adjustment mechanisms, combined with the spatiotemporal spike information extracted by the proposed model, to reconstruct the full texture of natural scenes in an ultra-high temporal resolution. Specifically, the proposed model consists of a motion local excitation layer, a spike refining layer and a visual reconstruction layer motivated by the bio-realistic leaky integrate-and-fire (LIF) neurons and synapse connection with spike-timing dependent plasticity (STDP) rule. To evaluate the performance, a spike dataset was constructed for normal and high-speed scenes in real-world recorded by the spike camera. The experimental results show that the proposed approach can reconstruct the visual images with 40,000 frames per second in both normal and high-speed scenes, while achieving high dynamic range and high image quality.


Algorithms , Neurons , Visual Perception/physiology , Retina , Models, Neurological
10.
J Vasc Surg ; 75(4): 1343-1348.e2, 2022 04.
Article En | MEDLINE | ID: mdl-34838611

OBJECTIVE: An aberrant right subclavian artery (ARSA) is the most common congenital anomaly of the aortic arch. A paucity of reported studies is available regarding the treatment of these patients. The purpose of the present study was to evaluate the contemporary management strategies and natural history of ARSA in these patients. METHODS: A single-center retrospective review of patients with a diagnosis of ARSA from 2009 to 2019 was performed. Computed tomography scans were analyzed, and the aortic and ARSA diameters were measured at 10 different segments. The demographic data, comorbidities, and operative interventions were collected. The patients were categorized into those who had undergone intervention and those who had undergone expectant management. Linear mixed effect models were used to estimate the annual ARSA diameter changes. RESULTS: A total of 30 patients with ARSA were identified, 17 (57%) of whom were women. The average age for the cohort was 54.5 ± 14.6 years. Of the 30 patients, 20 (67%) had undergone operative repair at presentation and 10 (33%) were initially observed. The most common presenting symptom was dysphagia (30%). Of the 10 patients who had been initially treated expectantly, 4 had subsequently required intervention. Of the 24 operative interventions, 13 (54%) were hybrid procedures involving right carotid-subclavian bypass or transposition and thoracic endovascular aortic repair. The mean diameter of ARSA at its origin was 20.4 ± 5.7 mm, and the mean cross-sectional aortic diameter at the level of the ARSA was 31.8 ± 8.5 mm for the entire cohort. For the patients who had initially been observed and had subsequently required intervention, the largest change in the ARSA cross-sectional diameter was observed 1 cm distally to the vessel ostium at a rate of 3.05 mm annually (95% confidence interval, 1.54-4.56; P < .001). No statistically significant changes in the annual growth rate of the aortic segments were observed in the entire cohort or for those patients who had undergone intervention (P > .05). CONCLUSIONS: The decision to intervene on an ARSA should be individualized by the presence of symptoms (eg, dysphagia lusoria) or complications (eg, dissection, concomitant aortic aneurysmal disease, enlarging Kommerell diverticulum). Asymptomatic patients with nonaneurysmal ARSA might not require any intervention and can be safely observed. Measurement of the cross-sectional ARSA diameter 1 cm distally to the ostium of the vessel might aid in the surveillance of vessel diameter changes. Additional studies are required to determine the specific size criteria as an indication for operative repair of asymptomatic Kommerell diverticulum.


Blood Vessel Prosthesis Implantation , Cardiovascular Abnormalities , Deglutition Disorders , Diverticulum , Endovascular Procedures , Adult , Aged , Aorta, Thoracic/abnormalities , Aorta, Thoracic/diagnostic imaging , Aorta, Thoracic/surgery , Blood Vessel Prosthesis Implantation/adverse effects , Cardiovascular Abnormalities/complications , Cardiovascular Abnormalities/diagnostic imaging , Cardiovascular Abnormalities/surgery , Deglutition Disorders/etiology , Deglutition Disorders/surgery , Diverticulum/surgery , Endovascular Procedures/adverse effects , Female , Humans , Male , Middle Aged , Subclavian Artery/abnormalities , Subclavian Artery/diagnostic imaging , Subclavian Artery/surgery , Treatment Outcome
11.
Oxid Med Cell Longev ; 2021: 6657529, 2021.
Article En | MEDLINE | ID: mdl-33986917

The cardioprotective effect of sevoflurane postconditioning (SPostC) is lost in diabetes that is associated with cardiac phosphatase and tensin homologue on chromosome 10 (PTEN) activation and phosphoinositide 3-kinase (PI3K)/Akt inactivation. T-LAK cell-originated protein kinase (TOPK), a mitogen-activated protein kinase- (MAPKK-) like serine/threonine kinase, has been shown to inactivate PTEN (phosphorylated status), which in turn activates the PI3K/Akt signaling (phosphorylated status). However, the functions of TOPK and molecular mechanism underlying SPostC cardioprotection in nondiabetes but not in diabetes remain unknown. We presumed that SPostC exerts cardioprotective effects by activating PTEN/PI3K/Akt through TOPK in nondiabetes and that impairment of TOPK/PTEN/Akt blocks diabetic heart sensitivity to SPostC. We found that in the nondiabetic C57BL/6 mice, SPostC significantly attenuated postischemic infarct size, oxidative stress, and myocardial apoptosis that was accompanied with enhanced p-TOPK, p-PTEN, and p-Akt. These beneficial effects of SPostC were abolished by either TOPK kinase inhibitor HI-TOPK-032 or PI3K/Akt inhibitor LY294002. Similarly, SPostC remarkably attenuated hypoxia/reoxygenation-induced cardiomyocyte damage and oxidative stress accompanied with increased p-TOPK, p-PTEN, and p-Akt in H9c2 cells exposed to normal glucose, which were canceled by either TOPK inhibition or Akt inhibition. However, either in streptozotocin-induced diabetic mice or in H9c2 cells exposed to high glucose, the cardioprotective effect of SPostC was canceled, accompanied by increased oxidative stress, decreased TOPK phosphorylation, and impaired PTEN/PI3K/Akt signaling. In addition, TOPK overexpression restored posthypoxic p-PTEN and p-Akt and decreased cell death and oxidative stress in H9c2 cells exposed to high glucose, which was blocked by PI3K/Akt inhibition. In summary, SPostC prevented myocardial ischemia/reperfusion injury possibly through TOPK-mediated PTEN/PI3K/Akt activation and impaired activation of this signaling pathway may be responsible for the loss of SPostC cardioprotection by SPostC in diabetes.


Diabetes Mellitus, Experimental/drug therapy , Hyperglycemia/enzymology , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Sevoflurane/pharmacology , Animals , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/enzymology , Heart/drug effects , Humans , Hyperglycemia/blood , Hyperglycemia/drug therapy , Male , Mice , Mice, Inbred C57BL , Mitogen-Activated Protein Kinase Kinases/metabolism , Myocardium/metabolism , Myocardium/pathology , Platelet Aggregation Inhibitors/pharmacology , Random Allocation , Rats , Signal Transduction/drug effects
14.
J Vasc Surg ; 70(5): 1463-1468, 2019 11.
Article En | MEDLINE | ID: mdl-31327603

OBJECTIVE: Endovascular aneurysm repair (EVAR) is associated with a greater risk of graft-related complications and need for secondary interventions compared with open repair. Type II endoleak (EL-2) is the most common complication. We examined the hypothesis that a functionally occluded inferior mesenteric artery (IMA) before EVAR was associated with fewer secondary interventions for EL-2. METHODS: All nonruptured abdominal aortic aneurysms (AAA) treated by EVAR using U.S. Food and Drug Administration-approved endografts from January 2005 to December 2017 were retrospectively reviewed, including computed tomography angiograms. Preoperative patency of the IMA and any secondary interventions performed after the index EVAR procedure were recorded. A functionally occluded IMA was defined as one that was (1) chronically occluded or severely stenosed on preoperative imaging or (2) coil embolized before EVAR. Secondary interventions for persistent EL-2 were indicated when AAA sac diameter increased by more than 5 mm. RESULTS: The study cohort comprised 490 patients (84 women) with a mean age of 74.8 ± 8.2 years. The mean preoperative AAA diameter was 5.6 ± 0.9 cm. One hundred twenty-nine patients (26.3%) died during follow-up. The mean follow-up of survivors was 38 months. Types (prevalence) of endoleak were I (2.4%), II (18.9%), III (0.7%), IV (0.5%), and V (0.2%). Patients with a functionally occluded IMA underwent significantly fewer secondary interventions for EL-2 compared with patients with a patent IMA (2.6% vs 7.1%; P = .020). All secondary interventions in the functionally occluded IMA group involved the lumbar arteries (LA). When the IMA was patent, secondary interventions were equally distributed between the LA and IMA. Logistic regression confirmed that a functionally patent IMA was associated with a greater number of secondary interventions for EL-2 (odds ratio, 3.0; 95% confidence interval, 1.2-7.5; P = .025). CONCLUSIONS: Patients with a functionally occluded IMA required significantly fewer secondary interventions for EL-2 after EVAR. In addition, the type of vessels intervened on were primarily LA. Among patients with a patent IMA, preoperative coil embolization may decrease secondary interventions and improve the long-term durability of EVAR.


Aortic Aneurysm, Abdominal/surgery , Blood Vessel Prosthesis Implantation/adverse effects , Endoleak/epidemiology , Endovascular Procedures/adverse effects , Mesenteric Artery, Inferior/physiopathology , Reoperation/statistics & numerical data , Aged , Aged, 80 and over , Aortic Aneurysm, Abdominal/complications , Aortic Aneurysm, Abdominal/mortality , Blood Vessel Prosthesis Implantation/instrumentation , Blood Vessel Prosthesis Implantation/methods , Endoleak/etiology , Endoleak/surgery , Endovascular Procedures/instrumentation , Endovascular Procedures/methods , Female , Follow-Up Studies , Humans , Male , Mesenteric Artery, Inferior/diagnostic imaging , Preoperative Period , Prevalence , Retrospective Studies , Risk Assessment , Risk Factors , Tomography, X-Ray Computed , Treatment Outcome , Ultrasonography, Doppler, Duplex , Vascular Patency/physiology
15.
IEEE Trans Image Process ; 23(10): 4511-26, 2014 Oct.
Article En | MEDLINE | ID: mdl-25167551

For the real-time and low-delay video surveillance and teleconferencing applications, the newly video coding standard HEVC can achieve much higher coding efficiency over H.264/AVC. However, we still argue that the hierarchical prediction structure in the HEVC low-delay encoder still does not fully utilize the special characteristics of surveillance and conference videos that are usually captured by stationary cameras. In this case, the background picture (G-picture), which is modeled from the original input frames, can be used to further improve the HEVC low-delay coding efficiency meanwhile reducing the complexity. Therefore, we propose an optimization method for the hierarchical prediction and coding in HEVC for these videos with background modeling. First, several experimental and theoretical analyses are conducted on how to utilize the G-picture to optimize the hierarchical prediction structure and hierarchical quantization. Following these results, we propose to encode the G-picture as the long-term reference frame to improve the background prediction, and then present a G-picture-based bit-allocation algorithm to increase the coding efficiency. Meanwhile, according to the proportions of background and foreground pixels in coding units (CUs), an adaptive speed-up algorithm is developed to classify each CU into different categories and then adopt different speed-up strategies to reduce the encoding complexity. To evaluate the performance, extensive experiments are performed on the HEVC test model. Results show our method can averagely save 39.09% bits and reduce the encoding complexity by 43.63% on surveillance videos, whereas those are 5.27% and 43.68% on conference videos.

16.
Presse Med ; 42(3): 269-79, 2013 Mar.
Article Fr | MEDLINE | ID: mdl-22770976

Anaphylactic reactions may be either of immune(allergy, usually IgE-mediated, sometimes IgG-mediated) or non-immune origin. The incidence of anaphylactic reactions during anaesthesia varies between countries ranging from 1/1250 to 1/13,000 per procedure. In France, the estimated incidence of allergic reactions is 100.6 [76.2-125.3]/million procedures with a high female predominance (male: 55.4 [42.0-69.0], female: 154.9 [117.2-193.1]). This predominance is not observed in children. In adults, the most frequently incriminated substances are neuromuscular blocking agents, followed by latex and antibiotics. The estimated incidence of allergic reactions to neuromuscular blocking agents is 184.0 [139.3-229.7]/million procedure. In most cases there is a close reaction between clinical symptoms and drug administration. When the reaction is delayed, occurring during the surgical procedure, a reaction involving latex, a vital dye, an antiseptic or a volume expanding fluid should be suspected. Reaction severity may vary. The most frequently reported initial symptoms are pulselessness, erythema, increased airway pressure, desaturation or decreased end-tidal CO2. Clinical symptoms may occur as an isolated condition, making proper diagnosis difficult. In some cases a cardiovascular arrest can be observed. Reaction mechanism identification relies on mediators (tryptase, histamine) measurement at the time of the reaction. In case of allergic reaction, the responsible drug can be identified by the detection of specific IgE using immunoassays or by skin tests performed 6 weeks after the reaction. Predictive allergy investigation to latex or anaesthetics in the absence of history of reaction should be restricted to at-risk patients. Premedication cannot prevent the onset of an allergic reaction. Providing a latex-free environment can be used for primary or secondary prevention. Treatment is based on allergen administration interruption, epinephrine administration in a titrated manner based on symptoms severity, and on volume expansion.


Anesthesia/adverse effects , Anesthetics/adverse effects , Drug Hypersensitivity/etiology , Female , Humans , Male , Risk Factors
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