Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
1.
Neural Regen Res ; 20(1): 234-241, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-38767488

ABSTRACT

JOURNAL/nrgr/04.03/01300535-202501000-00031/figure1/v/2024-05-14T021156Z/r/image-tiff Early identification and treatment of stroke can greatly improve patient outcomes and quality of life. Although clinical tests such as the Cincinnati Pre-hospital Stroke Scale (CPSS) and the Face Arm Speech Test (FAST) are commonly used for stroke screening, accurate administration is dependent on specialized training. In this study, we proposed a novel multimodal deep learning approach, based on the FAST, for assessing suspected stroke patients exhibiting symptoms such as limb weakness, facial paresis, and speech disorders in acute settings. We collected a dataset comprising videos and audio recordings of emergency room patients performing designated limb movements, facial expressions, and speech tests based on the FAST. We compared the constructed deep learning model, which was designed to process multi-modal datasets, with six prior models that achieved good action classification performance, including the I3D, SlowFast, X3D, TPN, TimeSformer, and MViT. We found that the findings of our deep learning model had a higher clinical value compared with the other approaches. Moreover, the multi-modal model outperformed its single-module variants, highlighting the benefit of utilizing multiple types of patient data, such as action videos and speech audio. These results indicate that a multi-modal deep learning model combined with the FAST could greatly improve the accuracy and sensitivity of early stroke identification of stroke, thus providing a practical and powerful tool for assessing stroke patients in an emergency clinical setting.

2.
Front Neurol ; 15: 1332940, 2024.
Article in English | MEDLINE | ID: mdl-38497036

ABSTRACT

Objective: This study aims to identify risk factors for vascular complications during non-emergency endovascular treatment in patients with internal carotid artery occlusion (ICAO) and to propose potential interventions. Method: A retrospective analysis of 92 patients with ICAO who received non-emergency endovascular treatment in our center from 1 January 2018 to 31 June 2023, was conducted. The correlation between intraoperative vascular complications and potential risk factors was studied, and interaction analysis was performed. Results: Our findings revealed that the use of non-neurology guide wires to open vessels (adjusted OR: 4.1, 95%CI: 1.3-12.8; p = 0.014) and glycosylated hemoglobin (HbA1c) ≥ 6.5 mmol/L (adjusted OR: 3.2, 95%CI: 1.2-8.9; p = 0.023) was significantly associated with vascular complications in non-emergency endovascular treatment of ICAO patients. The restricted cubic spline (RCS) showed that the higher the HbA1c level, the higher the risk of vascular complications. Conclusion: The use of non-neurology guide wires for vessel opening during non-emergency endovascular treatment in patients with ICAO increases the risk of vascular complications. Preoperative assessment and management of HbA1c levels can reduce the incidence of intraoperative vascular complications.

3.
J Neurointerv Surg ; 2023 Jul 27.
Article in English | MEDLINE | ID: mdl-37500477

ABSTRACT

BACKGROUND: Vasospasm and delayed cerebral ischemia (DCI) are the leading causes of morbidity and mortality after intracranial aneurysmal subarachnoid hemorrhage (aSAH). Vasospasm detection, prevention and management, especially endovascular management varies from center to center and lacks standardization. We aimed to evaluate this variability via an international survey of how neurointerventionalists approach vasospasm diagnosis and endovascular management. METHODS: We designed an anonymous online survey with 100 questions to evaluate practice patterns between December 2021 and September 2022. We contacted endovascular neurosurgeons, neuroradiologists and neurologists via email and via two professional societies - the Society of NeuroInterventional Surgery (SNIS) and the European Society of Minimally Invasive Neurological Therapy (ESMINT). We recorded the physicians' responses to the survey questions. RESULTS: A total of 201 physicians (25% [50/201] USA and 75% non-USA) completed the survey over 10 months, 42% had >7 years of experience, 92% were male, median age was 40 (IQR 35-46). Both high-volume and low-volume centers were represented. Daily transcranial Doppler was the most common screening method (75%) for vasospasm. In cases of symptomatic vasospasm despite optimal medical management, endovascular treatment was directly considered by 58% of physicians. The most common reason to initiate endovascular treatment was clinical deficits associated with proven vasospasm/DCI in 89%. The choice of endovascular treatment and its efficacy was highly variable. Nimodipine was the most common first-line intra-arterial therapy (40%). Mechanical angioplasty was considered the most effective endovascular treatment by 65% of neurointerventionalists. CONCLUSION: Our study highlights the considerable heterogeneity among the neurointerventional community regarding vasospasm diagnosis and endovascular management. Randomized trials and guidelines are needed to improve standard of care, determine optimal management approaches and track outcomes.

4.
Neuroradiology ; 62(10): 1323-1334, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32494963

ABSTRACT

PURPOSE: To evaluate the feasibility and safety of endovascular recanalization for symptomatic subacute and chronic internal carotid artery occlusion (ICAO); to propose a newly modified radiographic classification of ICAO that can rigorously identify suitable candidates for endovascular ICAO treatment. METHODS: We included 42 consecutive patients who had ICAO with ischaemic symptoms refractory to medical therapy. We examined the symptomatology, complications, follow-up results and radiographic images of ICAO receiving attempted endovascular treatment. We attempted to stratify all radiographic images into categories based on morphological occlusion patterns, occlusion segments and distal ICA reconstitution on digital subtraction angiography (DSA). RESULTS: Four types (A-D) of radiographic ICAO were identified. We redefined type B as having a tapered stump but no distal lumen. The rate of successful recanalization was 83.33% (35/42 ICAOs; type A, 18/20; type B, 7/10; type C, 10/11; type D, 0/1). The perioperative complication rate was 11.90% (5/42), including 3 asymptomatic distal embolisms, 1 symptomatic cerebral infarction and 1 asymptomatic carotid artery dissection. None of these technique-related complications led to severe neurological damage or death. Modified Rankin Scale (mRS) scores after 1-20 months of follow-up were significantly decreased in successfully revascularized patients (P < 0.001). There was no significant change in mRS scores in the 7 patients in whom recanalization failed (P > 0.05). CONCLUSIONS: Endovascular recanalization seems to achieve technical success and clinical improvement for symptomatic subacute and chronic ICAO. Additionally, our newly modified radiographic classification of ICAO may be valuable in assessing the technical feasibility and safety of procedures in symptomatic ICAO patients.


Subject(s)
Carotid Artery, Internal , Carotid Stenosis/diagnostic imaging , Carotid Stenosis/surgery , Endovascular Procedures/methods , Neuroimaging/methods , Adult , Aged , Feasibility Studies , Female , Humans , Male , Middle Aged , Patient Safety , Retrospective Studies
5.
Food Funct ; 10(12): 8310, 2019 12 11.
Article in English | MEDLINE | ID: mdl-31710079

ABSTRACT

Correction for 'Insights into melanoidin conversion into fluorescent nanoparticles in the Maillard reaction' by Dongmei Li et al., Food Funct., 2019, 10, 4414-4422.

6.
Food Funct ; 10(7): 4414-4422, 2019 Jul 17.
Article in English | MEDLINE | ID: mdl-31282903

ABSTRACT

The Maillard reaction is a well known chemical reaction in the food industry, in which melanoidins are generally considered as the final product. However, the exact final products of the Maillard reaction are far from being well understood. The conversion mechanism of melanoidins is of importance for explanation of the whole process of the Maillard reaction. In this paper, the conversion of melanoidins in the Maillard reaction was studied using glucose and lysine as raw materials. Our results showed that fluorescent nanoparticles (FNPs) can be formed after the hydrothermal reaction of melanoidins at 180 °C for 2, 4, 6 and 8 hours, respectively. Unlike melanoidins, the FNPs are highly water-soluble and strongly fluorescent and have a particle size of around 0.7-6.8 nm. X-ray photoelectron spectroscopy and 1H NMR spectroscopy analysis demonstrated that there are many functional structures like carboxyl, hydroxyl, aldehyde, amine and aromatic groups produced on the surface of the FNPs. Total elemental analysis indicated that the oxidization of the FNPs was intensified with the extension of reaction time. The thermogravimetric kinetics of the FNPs were significantly different from those of melanoidins. More heterocyclic and aromatic compounds were found in the pyrolysis products of the FNPs with the extension of reaction time. The results of this paper provided new insights into the conversion of melanoidins for further understanding of the Maillard reaction.


Subject(s)
Fluorescent Dyes/chemistry , Maillard Reaction , Nanoparticles/chemistry , Polymers/chemistry , Glucose/chemistry , Heterocyclic Compounds , Kinetics , Lysine , Magnetic Resonance Spectroscopy , Particle Size
7.
Ann Vasc Surg ; 58: 338-346, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30769077

ABSTRACT

BACKGROUND: The aims of this study were to explore (i) the dynamic changes in cerebral microbleeds (CMBs) in patients with symptomatic cerebral artery stenosis who received endovascular stent-assisted angioplasty and (ii) the risk factors associated with the new incidence of CMBs as well as whether CMBs increased the risk of vascular events in these patients. METHODS: Clinical information and magnetic resonance images were collected on admission and 3 months after endovascular stent-assisted angioplasty. Based on susceptibility-weighted imaging, the patients were divided into groups with or without newly developed CMBs, and between-group differences in risk factors were compared. We also compared whether CMBs increased the risk of vascular events among those patients. RESULTS: Seventy-three patients completed the relevant follow-up examinations. After an average follow-up period of 109 days, 7 (9.6%) patients showed new CMBs. A univariate analysis showed that the number of lacunar infarcts and the increase in systolic blood pressure were higher in patients with new CMBs than in those without new CMBs, and these differences were significant (P = 0.034, P = 0.001). Increased systolic blood pressure was an independent risk factor for developing new CMBs (P = 0.017). CONCLUSIONS: CMBs may be a continuously progressing cerebral small-vessel disease. The newly developed CMBs in patients with intracranial and/or extracranial stents were associated with increased systolic blood pressure but not with the number of baseline CMBs.


Subject(s)
Angioplasty/instrumentation , Cerebral Arterial Diseases/therapy , Cerebral Hemorrhage/etiology , Cerebral Small Vessel Diseases/therapy , Stents , Aged , Angiography, Digital Subtraction , Angioplasty/adverse effects , Blood Pressure , Cerebral Angiography/methods , Cerebral Arterial Diseases/complications , Cerebral Arterial Diseases/diagnostic imaging , Cerebral Arterial Diseases/physiopathology , Cerebral Hemorrhage/diagnostic imaging , Cerebral Hemorrhage/physiopathology , Cerebral Small Vessel Diseases/complications , Cerebral Small Vessel Diseases/diagnostic imaging , Cerebral Small Vessel Diseases/physiopathology , Diffusion Magnetic Resonance Imaging , Female , Follow-Up Studies , Humans , Male , Middle Aged , Risk Assessment , Risk Factors , Systole , Time Factors , Treatment Outcome
8.
Brain Behav ; 8(1): e00873, 2018 01.
Article in English | MEDLINE | ID: mdl-29568679

ABSTRACT

Background: Multiple studies suggest that internal carotid artery stenting can be performed safely in octogenarians with low periprocedural complication rates. However, great concern still exists as to whether these patients will gain long-term benefits from this procedure given their advanced age and uncertain life expectancy. We decided to conduct a retrospective study to determine short-and long-term clinical outcomes and to analyze survival duration in this population. Methods and Results: Sixty-nine consecutive elderly patients with either symptomatic or asymptomatic stenosis ≥70% underwent 86 procedures. Immediate and late outcomes, as well as survival data, were analyzed retrospectively. Mean age was 83.1 ± 2.7 years. Mean survival was 49.3 ± 10.1 months. A complete neurological assessment was obtained at 1 and 2 years in 100% of patients, at 3 years in 90.7% of patients and at 5 years in 84.8% of patients. Two major and one minor ischemic strokes occurred during the periprocedural period. No death, myocardial infarction or intracranial hemorrhage was recorded. The mean follow-up period was 55.4 ± 24.6 months. Four patients experienced a minimum of 1 year of follow-up, and the longest is 8 years. Among the patients with the longest follow-up time, 6 had ischemic strokes, of which 2 were fatal. In total, 17 deaths occurred. Four patients experienced dementia without stroke. Survival at 3 and 5 years was estimated to be 90% and 73%, respectively. Conclusion: This study demonstrated that stenting in octogenarians was safe and effective during the periprocedural period. Long-term follow-up showed a low rate of fatal and nonfatal stroke, and patients survived long enough to benefit from the procedure. However, it was associated with a relatively high rate of long-term event. Though carotid artery stenting is a minimally invasive procedure, it should still be performed with great caution and only in carefully selected patients. The present study suggested that in this age population, carotid artery stenting might be considered as a revascularization option.


Subject(s)
Blood Vessel Prosthesis Implantation/adverse effects , Carotid Stenosis , Life Expectancy , Long Term Adverse Effects/mortality , Postoperative Complications/epidemiology , Stents , Stroke , Aged, 80 and over , Blood Vessel Prosthesis Implantation/instrumentation , Blood Vessel Prosthesis Implantation/methods , Carotid Artery, Internal/pathology , Carotid Artery, Internal/surgery , Carotid Stenosis/diagnosis , Carotid Stenosis/mortality , Carotid Stenosis/surgery , China/epidemiology , Female , Humans , Male , Minimally Invasive Surgical Procedures , Patient Selection , Retrospective Studies , Stroke/epidemiology , Stroke/etiology , Survival Analysis
10.
Neurosci Lett ; 558: 26-30, 2014 Jan 13.
Article in English | MEDLINE | ID: mdl-24189491

ABSTRACT

Neuronal damage after transient cerebral ischemia is exacerbated by signaling pathways involving activated platelet-activating factor (PAF) and ameliorated by PAF-acetylhydrolase (PAF-AH); but whether cerebral neurons can be rescued by human recombinant PAF-AH (rPAF-AH) remains unknown. Adult male mice underwent a 60 min middle cerebral artery occlusion (MCAO) and reperfusion for 24h. Then, the mice received intravenous tail injections with different drugs. Neurological behavioral function was evaluated by Bederson's test, and cerebral infarction volume was assessed with tetrazolium chloride (TTC) staining. mRNA and protein expression levels of matrix metalloproteinase-2 (MMP-2, collagenase-1), MMP-9 (gelatinase-B), and vascular endothelial growth factor (VEGF) were determined by quantitative real-time PCR (RT-PCR) and western blot analysis, respectively. Compared with the vehicle group, rPAF-AH significantly improved sensorimotor function (42%, P=0.0001). The volume of non-infarcted brain tissue was increased by the rPAF-AH treatment (16.3±4.6% vs. 46.0±10.3%, respectively). rPAF-AH significantly reduced mRNA and protein levels of MMP-2 and MMP-9, but increased the mRNA (P<0.001) and protein levels (P<0.01) of VEGF. These results demonstrate that rPAF-AH provides neuroprotection against ischemic injury. Neuroprotection might be induced not only by decrease in MMP-2 and MMP-9 expression, but also by increased VEGF expression.


Subject(s)
1-Alkyl-2-acetylglycerophosphocholine Esterase/therapeutic use , Ischemic Attack, Transient/drug therapy , Neuroprotective Agents/therapeutic use , Animals , Behavior, Animal/drug effects , Brain/drug effects , Brain/metabolism , Brain/pathology , Cerebral Infarction/drug therapy , Cerebral Infarction/pathology , Humans , Ischemic Attack, Transient/pathology , Ischemic Attack, Transient/physiopathology , Male , Matrix Metalloproteinase 2/genetics , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase 9/metabolism , Mice , RNA, Messenger/metabolism , Recombinant Proteins/therapeutic use , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism
11.
Zhonghua Yi Xue Za Zhi ; 91(11): 766-8, 2011 Mar 22.
Article in Chinese | MEDLINE | ID: mdl-21600103

ABSTRACT

OBJECTIVE: To evaluate the correlation of collateral circulation with prognosis in patients with acute cerebral infarction. METHODS: A total of 260 patients with acute ischemic stroke within 1 week of symptom onset underwent digital subtraction angiogram (DSA). The National Institutes of Health Stroke Scale (NIHSS) scores were obtained at admission. And the Modified Rankin scores (mRS) were assessed at a 3-month follow-up. The follow-up data were acquired through clinic visits or telephone interviews. RESULTS: Among them, 86 were found to have intra- or extra-cranial culprit artery severe stenosis or occlusion. And 36 (75.00%) in 48 patients had collateral arterial circulation while 11 (28.64%) in 38 patients posterior circulation. There were statistical differences in the NIHSS scores at admission and favorite clinical outcome (mRS ≤ 2) at 3-month follow-up for patients with and without collateral circulation. CONCLUSION: DSA is the golden standard for the assessment of collateral circulation in patients with severe cerebral artery stenosis or occlusion. The prognosis is better in stroke patients with collateral circulation.


Subject(s)
Cerebral Infarction/physiopathology , Collateral Circulation , Aged , Angiography, Digital Subtraction , Carotid Stenosis/complications , Cerebral Infarction/complications , Cerebral Infarction/diagnostic imaging , Cerebrovascular Disorders/complications , Female , Humans , Male , Middle Aged , Prognosis , Treatment Outcome
12.
J Huazhong Univ Sci Technolog Med Sci ; 31(1): 67-72, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21336726

ABSTRACT

The curative efficacy of percutaneous transluminal angioplasty and stenting (PTAS) in the treatment of patients with ischemia cerebrovascular disease caused by artery stenosis was explored. The clinical data of 111 patients with ischemia cerebrovascular disease receiving PTAS in Guangdong Province General Hospital from Aug. 2007 to Nov. 2009 were retrospectively analyzed. In total 132 stents were implanted in the 111 patients. The mortality and rate of neural and non-neural complications were assessed perioperatively. Outcomes [including the frequency of transient ischemic attack (TIA), stroke, or death from vascular diseases) were assessed after operation. NIHSS rating was performed in all cases before and at first week, 6th month and 12th month after the operation. The PTAS success rate was 100%. The degree of stenosis was reduced after PTAS. The total complication rate during perioperative period was 15.3% (the rate of neural complications was 3.6%). Sixty-seven patients were followed up. Three patients (4.48%) developed cerebrovascular events within 1 month, containing one case of TIA, one case of ipsilateral mild stroke and one case of contralateral mild stroke. No severe stroke or death was observed. During a follow-up period of 12 months 7 patients had cerebrovascular events (10.44%), including 2 cases of ipsilateral TIA (2.99%), 2 cases of ipsilateral mild stroke and 2 cases of contralateral mild stroke (2.99%), one case of severe stroke (1.49%). In 13 patients receiving DSA re-examination one year after PTAS, 2 patients (15.38%) had in-stent restenosis. NIHSS scores were obviously decreased during a follow-up period as compared with those pre-operation (P<0.05). It was concluded that PTAS could significantly alleviate the neural function deficit of the patients with ischemia cerebrovascular disease. The success rate of PTAS was high, and the rate of complications was lower and the clinical outcomes were satisfactory. PTAS is a safe and effective therapeutic method, though the long-term outcomes need further study.


Subject(s)
Angioplasty , Brain Ischemia/therapy , Intracranial Arteriosclerosis/therapy , Ischemic Attack, Transient/therapy , Stents , Adult , Aged , Angiography, Digital Subtraction , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies
13.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-298666

ABSTRACT

The curative efficacy of percutaneous transluminal angioplasty and stenting (PTAS) in the treatment of patients with ischemia cerebrovascular disease caused by artery stenosis was explored.The clinical data of 111 patients with ischemia cerebrovascular disease receiving PTAS in Guangdong Province General Hospital from Aug.2007 to Nov.2009 were retrospectively analyzed.In total 132 stents were implanted in the 111 patients.The mortality and rate of neural and non-neural complications were assessed perioperatively.Outcomes [including the frequency of transient ischemic attack (TIA),stroke,or death from vascular diseases) were assessed after operation.NIHSS rating was performed in all cases before and at first week,6th month and 12th month after the operation.The PTAS success rate was 100%.The degree of stenosis was reduced after PTAS.The total complication rate during perioperative period was 15.3% (the rate of neural complications was 3.6%).Sixty-seven patients were followed up.Three patients (4.48%) developed cerebrovascular events within 1 month,containing one case of TIA,one case of ipsilateral mild stroke and one case of contralateral mild stroke.No severe stroke or death was observed.During a follow-up period of 12 months 7 patients had cerebrovascular events (10.44%),including 2 cases of ipsilateral TIA (2.99%),2 cases of ipsilateral mild stroke and 2 cases of contralateral mild stroke (2.99%),one case of severe stroke (1.49%).In 13 patients receiving DSA re-examination one year after PTAS,2 patients (15.38%) had in-stent restenosis.NIHSS scores were obviously decreased during a follow-up period as compared with those pre-operation (P<0.05).It was concluded that PTAS could significantly alleviate the neural function deficit of the patients with ischemia cerebrovascular disease.The success rate of PTAS was high,and the rate of complications was lower and the clinical outcomes were satisfactory.PTAS is a safe and effective therapeutic method,though the long-term outcomes need further study.

15.
Cancer Lett ; 279(1): 47-56, 2009 Jun 28.
Article in English | MEDLINE | ID: mdl-19203829

ABSTRACT

Activated mTOR was implicated to play a role in the carcinogenesis of nasopharyngeal carcinoma (NPC). However, the mechanism of activated mTOR/Complex1(mTORC1) signaling pathway in NPC development has not been well established. In this study, we correlated the expression of mTORC1 signal molecules and Cyclin D1 in NPC. We also investigated the effect of blocking mTORC1 signal with rapamycin and mTOR siRNA on Cyclin D1 expression in CNE-2 cells, as well as cell apoptosis and viability. We found a positive association of mTORC1 signal molecules and Cyclin D1 in NPC. Also, we found blockage mTORC1 inhibited Cyclin D1 expression in CNE-2 cells and enhanced cell apoptosis. Our results suggested that mTORC1 signal pathway might be a potential target for NPC therapy.


Subject(s)
Carcinoma/metabolism , Cyclin D1/metabolism , Nasopharyngeal Neoplasms/metabolism , Protein Kinases/metabolism , Signal Transduction , Adaptor Proteins, Signal Transducing/metabolism , Adult , Apoptosis , Carcinoma/pathology , Carcinoma/therapy , Case-Control Studies , Cell Cycle Proteins , Cell Line, Tumor , Cell Survival , Dose-Response Relationship, Drug , Female , Humans , Male , Middle Aged , Multiprotein Complexes/metabolism , Nasopharyngeal Neoplasms/pathology , Nasopharyngeal Neoplasms/therapy , Phosphoproteins/metabolism , Phosphorylation , Protein Kinases/genetics , RNA Interference , RNA, Small Interfering/metabolism , Signal Transduction/drug effects , Sirolimus/pharmacology , TOR Serine-Threonine Kinases , Time Factors , Transfection , Up-Regulation
16.
Stroke ; 40(3): 973-6, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19131653

ABSTRACT

BACKGROUND AND PURPOSE: MIF has been implicated to function in many inflammatory processes. This study examined whether MIF expression was affected in stroke and its underlying molecular mechanism. METHODS: ELISA and qRT-PCR were used to detect MIF protein and mRNA in PBMCs from stroke patients, the ischemic rat brains, and controls. A MIF promoter assay under hypoxia was performed. RESULTS: MIF protein and mRNA were significantly increased in stroke patients. Increasing levels of MIF were correlated to the severity of stroke and peaked 24 hours after stroke. MIF was significantly upregulated in focal ischemic rat brains. The activity of the human MIF promoter was significantly increased under hypoxia compared to normoxia. CONCLUSIONS: MIF gene expression is upregulated after stroke, and hypoxia signaling plays an important role in upregulation of MIF expression under stroke.


Subject(s)
Macrophage Migration-Inhibitory Factors/biosynthesis , Stroke/genetics , Aged , Animals , Base Sequence , Blotting, Western , Brain Ischemia/genetics , Brain Ischemia/metabolism , Enzyme-Linked Immunosorbent Assay , Female , Humans , Macrophage Migration-Inhibitory Factors/genetics , Male , Molecular Sequence Data , Promoter Regions, Genetic/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Rats , Reverse Transcriptase Polymerase Chain Reaction , Sequence Tagged Sites , Up-Regulation
17.
Acta Radiol ; 48(7): 788-97, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17729012

ABSTRACT

BACKGROUND: A longstanding hypothesis that correlates fluid dynamic forces and atherosclerotic disease has led to numerous analytical, numerical, and experimental studies over the years because it is very difficult to measure the hemodynamic variables of blood in vivo. PURPOSE: To investigate the technique of visualization and quantitation of hemodynamic variables at carotid artery bifurcation in vivo by combining computational fluid dynamics (CFD) and vascular imaging. MATERIAL AND METHODS: Twenty-six healthy volunteers underwent magnetic resonance (MR) angiography of the bilateral carotid artery by a 3.0T whole-body scanner. Hemodynamic variables at these carotid bifurcations were calculated and visualized by combining vascular imaging post-processing and CFD. RESULTS: The average velocity of the carotid bifurcation in the systolic phase and the diastolic phase was 0.46+/-0.24 m/s and 0.23+/-0.05 m/s, respectively. Eddy current and back flows were observed at bifurcation and the lateral part of the proximal internal carotid arteries (ICA) and external carotid arteries (ECA), and the shapes of them changed with phases of the cardiac cycle, which were significant at the middle of the systolic phase and faded out quickly downstream of the ICA and ECA. The average range of wall shear stress (WSS) at the bifurcation was 4.36+/-1.32 Pa, and the maximum WSS was 18.02+/-4.11 Pa. The WSS map revealed a large region of low WSS at the carotid bulb and extended to the outer wall in the proximal end of the ICA (the lowest value was below 0.5 Pa), and there was also a small region of low WSS at the outer wall in the proximal end of the ECA. CONCLUSION: CFD combined with vascular imaging can calculate and visualize hemodynamic variables at carotid bifurcation in vivo individually.


Subject(s)
Blood Flow Velocity/physiology , Carotid Arteries/physiology , Hemorheology , Magnetic Resonance Angiography , Regional Blood Flow/physiology , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Reference Values , Shear Strength , Vascular Resistance/physiology
19.
Zhonghua Yi Xue Za Zhi ; 84(23): 2002-6, 2004 Dec 02.
Article in Chinese | MEDLINE | ID: mdl-15730817

ABSTRACT

OBJECTIVE: To preliminarily evaluate the immunity and safety of the recombinant adenoviruses expressing rotavirus structural proteins VP7 and VP6 in rhesus monkeys to lay a foundation for the development of novel genetic engineering vaccine against rotavirus. METHODS: Baby monkeys were immunized with the recombinant adenoviruses intranasally or orally. Serum IgG against rotavirus was measured with ELISA. During the course of the immunization, besides the daily monitoring of body temperature, weight and clinical symptoms, the routine blood and urine tests and liver and kidney function tests were also conducted. RESULTS: Monkeys immunized via intranasal or oral routes could both generate serum IgG against rotavirus. During the immunization, the temperature of monkeys was normal and body weight raise stably. Both routine blood and urine tests and liver and kidney function tests showed no significant alteration compared with the control group. CONCLUSION: The immunization with the recombinant adenoviruses expressing rotavirus antigens is able to induce rotavirus specific efficient immune responses and is safe to baby rhesus monkeys. The preliminary results implied that the recombinant adenoviruses could be an ideal vaccine for rotavirus and lay a foundation for further studies.


Subject(s)
Adenoviridae/genetics , Antigens, Viral/immunology , Capsid Proteins/immunology , Rotavirus/genetics , Vaccines, Synthetic , Adenoviridae/metabolism , Animals , Antibodies, Viral/biosynthesis , Antigens, Viral/biosynthesis , Antigens, Viral/genetics , Capsid Proteins/biosynthesis , Capsid Proteins/genetics , Genetic Engineering , Macaca mulatta , Rotavirus/immunology , Rotavirus Infections/immunology , Rotavirus Infections/prevention & control , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/immunology , Viral Structural Proteins/genetics
SELECTION OF CITATIONS
SEARCH DETAIL
...