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1.
Nucleic Acids Res ; 2024 Apr 27.
Article En | MEDLINE | ID: mdl-38676949

DNA, beyond its canonical B-form double helix, adopts various alternative conformations, among which the i-motif, emerging in cytosine-rich sequences under acidic conditions, holds significant biological implications in transcription modulation and telomere biology. Despite recognizing the crucial role of i-motifs, predictive software for i-motif forming sequences has been limited. Addressing this gap, we introduce 'iM-Seeker', an innovative computational platform designed for the prediction and evaluation of i-motifs. iM-Seeker exhibits the capability to identify potential i-motifs within DNA segments or entire genomes, calculating stability scores for each predicted i-motif based on parameters such as the cytosine tracts number, loop lengths, and sequence composition. Furthermore, the webserver leverages automated machine learning (AutoML) to effortlessly fine-tune the optimal i-motif scoring model, incorporating user-supplied experimental data and customised features. As an advanced, versatile approach, 'iM-Seeker' promises to advance genomic research, highlighting the potential of i-motifs in cell biology and therapeutic applications. The webserver is freely available at https://im-seeker.org.

2.
Front Neurosci ; 18: 1371319, 2024.
Article En | MEDLINE | ID: mdl-38545602

Investigation on long-term effects of robot-assisted poststroke rehabilitation is challenging because of the difficulties in administration and follow-up of individuals throughout the process. A mobile hybrid neuromuscular electrical stimulation (NMES)-robot, i.e., exoneuromusculoskeleton (ENSM) was adopted for a single-group trial to investigate the long-term effects of the robot-assisted self-help telerehabilitation on upper limb motor function after stroke. Twenty-two patients with chronic stroke were recruited to attend a 20-session telerehabilitation program assisted by the wrist/hand module of the ENMS (WH-ENMS). Participants were evaluated before, after, as well as at 3 months and 6 months after the training. The primary outcome measure was the Fugl-Meyer Assessment-Upper Extremity (FMA-UE), supplemented by secondary outcome measures of the FMA-UE of the shoulder and elbow (FMA shoulder/elbow), the FMA-UE of the wrist and hand (FMA wrist/hand), the Modified Ashworth Scale (MAS), the Action Research Arm Test (ARAT), the Wolf Motor Function Test (WMFT), the Functional Independence Measure (FIM), as well as electromyography (EMG) and kinematic measurements. Twenty participants completed the telerehabilitation program, with 19 returning for a 3-month follow-up, and 18 for a 6-month follow-up. Significantly improved clinical scores were observed after the training (p ≤ 0.05). These improvements were maintained after 6 months in the FMA-UE, FMA shoulder/elbow, MAS at the wrist flexor, WMFT score, WMFT time, and FIM (p ≤ 0.05). The maintained improvements in motor function were attributed to reduced muscular compensation, as indicated by EMG and kinematic parameters. The WH-ENMS-assisted self-help telerehabilitation could achieve long-lasting rehabilitative effects in chronic stroke.

3.
Nucleic Acids Res ; 52(5): 2188-2197, 2024 Mar 21.
Article En | MEDLINE | ID: mdl-38364855

i-Motifs (iMs), are secondary structures formed in cytosine-rich DNA sequences and are involved in multiple functions in the genome. Although putative iM forming sequences are widely distributed in the human genome, the folding status and strength of putative iMs vary dramatically. Much previous research on iM has focused on assessing the iM folding properties using biophysical experiments. However, there are no dedicated computational tools for predicting the folding status and strength of iM structures. Here, we introduce a machine learning pipeline, iM-Seeker, to predict both folding status and structural stability of DNA iMs. The programme iM-Seeker incorporates a Balanced Random Forest classifier trained on genome-wide iMab antibody-based CUT&Tag sequencing data to predict the folding status and an Extreme Gradient Boosting regressor to estimate the folding strength according to both literature biophysical data and our in-house biophysical experiments. iM-Seeker predicts DNA iM folding status with a classification accuracy of 81% and estimates the folding strength with coefficient of determination (R2) of 0.642 on the test set. Model interpretation confirms that the nucleotide composition of the C-rich sequence significantly affects iM stability, with a positive correlation with sequences containing cytosine and thymine and a negative correlation with guanine and adenine.


DNA , Machine Learning , Nucleotide Motifs , Humans , Base Sequence , Cytosine/chemistry , DNA/chemistry , DNA/genetics
4.
Bioengineering (Basel) ; 10(8)2023 Aug 18.
Article En | MEDLINE | ID: mdl-37627861

Rehabilitation robots are helpful in poststroke telerehabilitation; however, their feasibility and rehabilitation effectiveness in clinical settings have not been sufficiently investigated. A non-randomized controlled trial was conducted to investigate the feasibility of translating a telerehabilitation program assisted by a mobile wrist/hand exoneuromusculoskeleton (WH-ENMS) into routine clinical services and to compare the rehabilitative effects achieved in the hospital-service-based group (n = 12, clinic group) with the laboratory-research-based group (n = 12, lab group). Both groups showed significant improvements (p ≤ 0.05) in clinical assessments of behavioral motor functions and in muscular coordination and kinematic evaluations after the training and at the 3-month follow-up, with the lab group demonstrating better motor gains than the clinic group (p ≤ 0.05). The results indicated that the WH-ENMS-assisted tele-program was feasible and effective for upper limb rehabilitation when integrated into routine practice, and the quality of patient-operator interactions physically and remotely affected the rehabilitative outcomes.

5.
Nucleic Acids Res ; 51(D1): D126-D134, 2023 01 06.
Article En | MEDLINE | ID: mdl-36243987

RNA G-quadruplex (rG4) is a vital RNA tertiary structure motif that involves the base pairs on both Hoogsteen and Watson-Crick faces of guanines. rG4 is of great importance in the post-transcriptional regulation of gene expression. Experimental technologies have advanced to identify in vitro and in vivo rG4s across diverse transcriptomes. Building on these recent advances, here we present G4Atlas, the first transcriptome-wide G-quadruplex database, in which we have collated, classified, and visualized transcriptome rG4 experimental data, generated from rG4-seq, chemical profiling and ligand-binding methods. Our comprehensive database includes transcriptome-wide rG4s generated from 82 experimental treatments and 238 samples across ten species. In addition, we have also included RNA secondary structure prediction information across both experimentally identified and unidentified rG4s to enable users to display any potential competitive folding between rG4 and RNA secondary structures. As such, G4Atlas will enable users to explore the general functions of rG4s in diverse biological processes. In addition, G4Atlas lays the foundation for further data-driven deep learning algorithms to examine rG4 structural features.


G-Quadruplexes , Transcriptome , Algorithms , Guanine , RNA/genetics , RNA/chemistry , Transcriptome/genetics , Atlases as Topic
6.
Front Rehabil Sci ; 4: 1329927, 2023.
Article En | MEDLINE | ID: mdl-38259875

Stroke rehabilitation, which demands consistent, intensive, and adaptable intervention in the long term, faced significant challenges due to the COVID-19 pandemic. During this time, telerehabilitation emerged as a noteworthy complement to traditional rehabilitation services, offering the convenience of at-home care delivery and overcoming geographical and resource limitations. Self-help rehabilitation robots deliver repetitive and intensive physical assistance, thereby alleviating the labor burden. However, robots have rarely demonstrated long-term readiness for poststroke telerehabilitation services. The transition from research trials to general clinical services presents several challenges that may undermine the rehabilitative gains observed in these studies. This perspective discusses the technological readiness of personal use robots in the context of telerehabilitation and identifies the potential challenges for their clinical translation. The goal is to leverage technology to seamlessly integrate it into standard clinical workflows, ultimately enhancing the outcomes of stroke rehabilitation.

7.
Front Neurorobot ; 15: 648855, 2021.
Article En | MEDLINE | ID: mdl-34335219

Background: Surface electromyography (sEMG) based robot-assisted rehabilitation systems have been adopted for chronic stroke survivors to regain upper limb motor function. However, the evaluation of rehabilitation effects during robot-assisted intervention relies on traditional manual assessments. This study aimed to develop a novel sEMG data-driven model for automated assessment. Method: A data-driven model based on a three-layer backpropagation neural network (BPNN) was constructed to map sEMG data to two widely used clinical scales, i.e., the Fugl-Meyer Assessment (FMA) and the Modified Ashworth Scale (MAS). Twenty-nine stroke participants were recruited in a 20-session sEMG-driven robot-assisted upper limb rehabilitation, which consisted of hand reaching and withdrawing tasks. The sEMG signals from four muscles in the paretic upper limbs, i.e., biceps brachii (BIC), triceps brachii (TRI), flexor digitorum (FD), and extensor digitorum (ED), were recorded before and after the intervention. Meanwhile, the corresponding clinical scales of FMA and MAS were measured manually by a blinded assessor. The sEMG features including Mean Absolute Value (MAV), Zero Crossing (ZC), Slope Sign Change (SSC), Root Mean Square (RMS), and Wavelength (WL) were adopted as the inputs to the data-driven model. The mapped clinical scores from the data-driven model were compared with the manual scores by Pearson correlation. Results: The BPNN, with 15 nodes in the hidden layer and sEMG features, i.e., MAV, ZC, SSC, and RMS, as the inputs to the model, was established to achieve the best mapping performance with significant correlations (r > 0.9, P < 0.001), according to the FMA. Significant correlations were also obtained between the mapped and manual FMA subscores, i.e., FMA-wrist/hand and FMA-shoulder/elbow, before and after the intervention (r > 0.9, P < 0.001). Significant correlations (P < 0.001) between the mapped and manual scores of MASs were achieved, with the correlation coefficients r = 0.91 at the fingers, 0.88 at the wrist, and 0.91 at the elbow after the intervention. Conclusion: An sEMG data-driven BPNN model was successfully developed. It could evaluate upper limb motor functions in chronic stroke and have potential application in automated assessment in post-stroke rehabilitation, once validated with large sample sizes. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02117089.

8.
Plant Divers ; 43(3): 198-205, 2021 Jun.
Article En | MEDLINE | ID: mdl-34195504

The phylogenetic position of the monotypic woody Parapteropyrum (Polygonaceae) remains controversial. Parapteropyrum has been thought to be closely related to the woody genera of the tribe Atraphaxideae, although some evidence indicates that it nests within the herbal buckwheat genus Fagopyrum of tribe Polygoneae. In this study, we used plastome data to determine the phylogenetic position of Parapteropyrum (Fagopyrum) tibeticum. Different reference species were used to assemble plastomes of three species currently placed in the tribe Ataphaxideae: Parapteropyrum (Fagopyrum) tibeticum, Atraphaxis bracteata and Calligonum ebinuricum. Once assembled, plastomes were characterized and compared to plastomes of 12 species across the family Polygonaceae. Phylogenetic analyses of Polygonaceae were performed using whole plastome, all plastome genes, and single-copy genes. Plastomes assembled using different reference plastomes did not differ; however, annotations showed small variation. Plastomes of Parapteropyrum (Fagopyrum) tibeticum, A. bracteata and C. ebinuricum have the typical quadripartite structure with lengths between 159,265 bp and 164,270 bp, and a total number of plastome genes of about 130. Plastome microsatellites (SSR) ranged in number from 48 to 77. Maximum Likelihood and Bayesian analyses of three plastome data sets consistently nested Parapteropyrum within the genus Fagopyrum. Furthermore, our analyses indicated that sampled woody genera of the family Polygonaceae are polyphyletic. Our study provides strong evidence that the woody Parapteropyrum tibeticum, which is distantly related to woody genera sampled here, should be taxonomically placed under Fagopyrum as Fagopyrum tibeticum.

9.
Mitochondrial DNA B Resour ; 5(3): 3727-3729, 2020 Nov 13.
Article En | MEDLINE | ID: mdl-33367078

Nannoglottis ravida is an extremely endangered species in the Qinghai-Tibet Plateau. Based on the second-generation high-throughput genome sequencing, we assembled the plastome of this species. The length of the total plastome is 152,324 bp with a typical quadripartite structure including a large single-copy region of 83,708 bp, a small single-copy region of 29,882 bp and two reverse repeat regions of 19,367 bp respectively. A total of 131 genes were annotated including 85 protein-coding genes (PCG), 36 tRNA genes, 8 rRNA genes and 2 pseudogenes. The constructed phylogenetic tree with other species of two tribes Senecioneae and Astereae based on plastomes suggests that N. ravida has a close relationship with the Astereae, but diverged early from this tribe.

10.
Comput Assist Surg (Abingdon) ; 24(sup1): 105-112, 2019 10.
Article En | MEDLINE | ID: mdl-30760103

Three different types of synchronous control methods based on physiological parameters, electrocardiogram (ECG) and fixed systole, ECG and aortic pressure, and ECG and phonocardiogram (PCG) were used to trigger a proposed intra-ventricular assist device (iVAD). The ECG, aortic pressure, and PCG were processed, respectively, and featured characteristics were extracted to trigger the iVAD-experimented in vitro circulation system in the laboratory. The data showed that all three types of synchronous control methods produced trigger pulses synchronously and that the iVAD synchronously beat with the native heart. The multi-cycle data demonstrated that the synchronous delay time of the proposed iVAD during systole and diastole was separately stabilized at a certain time. This study showed that the combination of three synchronization methods can be applied to the iVAD to improve the reliability of synchronization.


Arterial Pressure , Electrocardiography , Heart-Assist Devices , Models, Cardiovascular , Phonocardiography , Humans
11.
Comput Assist Surg (Abingdon) ; 24(sup1): 89-95, 2019 10.
Article En | MEDLINE | ID: mdl-30741034

A novel pulsatile assist device, intra-ventricular assist device, was proposed to address various disadvantages existing in conventional pulsatile assist device, such as the large size, accessories and reduced pulsatility. The assist device was designed, fabricated and implanted into the sac from left ventricular apex in a home-designed mock circulatory system. In vitro test was carried out and results demonstrated that the response time did not vary with the heart rate, and co-pulsatiled synchronously with native heart by electrocardiograph. The key parameter, stroke volume of proposed device was precisely measured under different afterloads (60, 80, 100, and 120 mmHg), drive pressure (from 90 to 300 mmHg at 30 mmHg intervals), and heart rate (45-150 beats per minute). The measurement results revealed that the output characteristics of device, stroke volume increased with increasing drive pressure but decreased with increasing peripheral resistance, were consistent with the native heart. The proposed pump was then coupled with mock system that was set to a heart failure mode and the circulatory responses were tested. Results showed that the device improved left ventricular pressure from 106 to 158 mmHg, and stroke volume from 25.5 to 44 ml at 90 bpm.


Heart-Assist Devices , Models, Cardiovascular , Electrocardiography , Heart Rate , Humans , Stroke Volume
12.
Technol Health Care ; 26(S1): 471-479, 2018.
Article En | MEDLINE | ID: mdl-29758970

BACKGROUND: A novel intra-ventricular assist device (iVAD) was established as a new pulsatile assist device to address various disadvantages, such as bulky configuration and reduced arterial pulsatility, observed in conventional ventricular assist devices. OBJECTIVE: Analyzed the native left ventricular stroke volume (SV) after iVAD support in vitro. METHODS: The SV of iVAD was examined in a home-designed mock circulatory system (MCS) at different heart rates and drive pressures and the SV of a failure ventricle was examined with iVAD at 75, 90, 120 bpm and 120-180 mmHg drive pressure after iVAD support. Data pertaining to native left ventricular SV before and after iVAD support were compared. RESULTS: The native ventricular SV was improved by iVAD when its drive pressure (DP) was slightly greater than that of the mock system. Conversely, the native ventricular SV was decreased when DP was much greater than that (150 mmHg) of MCS. A high DP had a significant effect on SV. CONCLUSIONS: The proposed device improved the dysfunctional native left ventricular SV when DP of iVAD was slightly greater than that of MCS. However, iVAD reduced the SV when the drive pressure was greater than that of MCS.


Heart Failure/surgery , Heart Ventricles/physiopathology , Heart-Assist Devices , Models, Cardiovascular , Stroke Volume/physiology , Equipment Design , Heart Failure/physiopathology , Humans , Pulsatile Flow
13.
Comput Assist Surg (Abingdon) ; 22(sup1): 278-285, 2017 12.
Article En | MEDLINE | ID: mdl-29096553

We introduce and investigate a method to identify the feature point of an electrocardiogram (ECG) to provide real-time and accurate trigger signals for pulsatile ventricular assist devices (PVADs). An important part of this method is an improved data processing algorithm, in which a differential calculator and another a low-pass filtering were added to avoid drift in the original signal and systematically delay caused by physical devices. The method was systematically illustrated in this article and a test-setup was built based on the LabVIEW program development environment. Both simulations and experiments were carried out to demonstrate the merits of the method. Simulated results based on four typical pathological ECG signals confirm the robustness and adaptability of this method. Experimental results verified the benefits of this method with regard to increased accuracy that can pick up the interested signal accurately in a degree of larger than 99%. This improved technology proposed in this research will be greatly beneficial to simultaneous triggering in VADs and eventually to the heart failure recovery.


Algorithms , Electrocardiography/methods , Heart Failure/surgery , Heart-Assist Devices , Pulsatile Flow/physiology , Heart Failure/diagnostic imaging , Humans , Quality Improvement , Simulation Training
14.
Comput Assist Surg (Abingdon) ; 22(sup1): 221-231, 2017 12.
Article En | MEDLINE | ID: mdl-29072502

Ventricular assist devices (LVADs) are increasingly recognized for supporting blood circulation in heart failure patients who are non-transplant eligible. Because of its volume, the traditional pulsatile device is not easy to implant intracorporeally. Continuous flow LVADs (CF-LVADs) reduce arterial pulsatility and only offer continuous flow, which is different from physiological flow, and may cause long-term complications in the cardiovascular system. The aim of this study was to design a new pulsatile assist device that overcomes this disadvantage, and to test this device in the cardiovascular system. Firstly, the input and output characteristics of the new device were tested in a simple cardiovascular mock system. A detailed mathematical model was established by fitting the experimental data. Secondly, the model was tested in four pathological cases, and was simulated and coupled with a fifth-order cardiovascular system and a new device model using Matlab software. Using assistance of the new device, we demonstrated that the left ventricle pressure, aortic pressure, and aortic flow of heart failure patients improved to the levels of a healthy individual. Especially, in state IV level heart failure patients, the systolic blood pressure increased from 81.34 mmHg to 132.1 mmHg, whereas the diastolic blood pressure increased from 54.28 mmHg to 78.7 mmHg. Cardiac output increased from 3.21 L/min to 5.16 L/min. The newly-developed assist device not only provided a physiological flow that was similar to healthy individuals, but also effectively improved the ability of the pathological ventricular volume. Finally, the effects of the new device on other hemodynamic parameters are discussed.


Heart Failure/surgery , Heart-Assist Devices , Hemodynamics/physiology , Pulsatile Flow/physiology , Cardiac Output/physiology , Computer Simulation , Equipment Design , Humans , Models, Cardiovascular , Normal Distribution
15.
J Neuroeng Rehabil ; 14(1): 34, 2017 04 26.
Article En | MEDLINE | ID: mdl-28446181

BACKGROUND: It is a challenge to reduce the muscular discoordination in the paretic upper limb after stroke in the traditional rehabilitation programs. METHOD: In this study, a neuromuscular electrical stimulation (NMES) and robot hybrid system was developed for multi-joint coordinated upper limb physical training. The system could assist the elbow, wrist and fingers to conduct arm reaching out, hand opening/grasping and arm withdrawing by tracking an indicative moving cursor on the screen of a computer, with the support from the joint motors and electrical stimulations on target muscles, under the voluntary intention control by electromyography (EMG). Subjects with chronic stroke (n = 11) were recruited for the investigation on the assistive capability of the NMES-robot and the evaluation of the rehabilitation effectiveness through a 20-session device assisted upper limb training. RESULTS: In the evaluation, the movement accuracy measured by the root mean squared error (RMSE) during the tracking was significantly improved with the support from both the robot and NMES, in comparison with those without the assistance from the system (P < 0.05). The intra-joint and inter-joint muscular co-contractions measured by EMG were significantly released when the NMES was applied to the agonist muscles in the different phases of the limb motion (P < 0.05). After the physical training, significant improvements (P < 0.05) were captured by the clinical scores, i.e., Modified Ashworth Score (MAS, the elbow and the wrist), Fugl-Meyer Assessment (FMA), Action Research Arm Test (ARAT), and Wolf Motor Function Test (WMFT). CONCLUSIONS: The EMG-driven NMES-robotic system could improve the muscular coordination at the elbow, wrist and fingers. TRIAL REGISTRATION: ClinicalTrials.gov. NCT02117089 ; date of registration: April 10, 2014.


Electric Stimulation , Exoskeleton Device , Muscle, Skeletal , Robotics , Stroke Rehabilitation/instrumentation , Upper Extremity , Adult , Aged , Chronic Disease , Elbow Joint/innervation , Elbow Joint/physiology , Female , Finger Joint/innervation , Finger Joint/physiology , Humans , Male , Middle Aged , Paresis/etiology , Paresis/physiopathology , Paresis/rehabilitation , Physical Education and Training , Treatment Outcome , Wrist Joint/innervation , Wrist Joint/physiology
16.
J Mol Med (Berl) ; 91(1): 37-47, 2013 Jan.
Article En | MEDLINE | ID: mdl-22772377

Excessive activation of the transforming growth factor beta signaling pathway and disorganized cellular skeleton caused by genetic mutations are known to be responsible for the inherited thoracic aortic aneurysms and dissections (TAAD), a life-threatening vascular disease. To investigate the genotype-phenotype correlation, we screened genetic mutations of fibrillin-1 (FBN1), transforming growth factor-ß receptor-1 (TGFBR1) and transforming growth factor-ß receptor-2 (TGFBR2) for TAAD in 7 affected families and 22 sporadic patients. Of 19 potential mutations identified in FBN1, 11 appeared novel while the others were recurrent. Two mutations were detected in TGFBR2. Eight patients carried no mutation in either of these genes. Characterization of FBN1 c.5917+6T>C in transfected HEK293 cells demonstrated that it caused skipping of exon 47, leading to the loss of the 33th calcium binding epidermal growth factor-like domain associated with Marfan syndrome. Compared with exon 46, skipping of 47 did not cause patients ectopia lentis in all carriers. To correlate genotypes with phenotypes in different human ancestries, we reviewed the published mutational studies on FBN1 and found that the probability of cardiovascular defects were significantly increased in Chinese patients with premature termination codon or splicing mutations than those with missense mutations (91.7 % vs 54.2 %, P = 0.0307) or with noncysteine-involved point mutations than those with cysteine-involved mutations (88.9 % vs 33.3 %, P = 0.0131). Thus, we conclude that exon 47 skipping of FBN1 leads preferentially to cardiovascular defects and human ancestries influence genotype-phenotype correlation in TAAD.


Aorta, Thoracic/metabolism , Aortic Aneurysm, Thoracic/genetics , Aortic Dissection/genetics , Microfilament Proteins/genetics , Adolescent , Adult , Aortic Dissection/ethnology , Aortic Dissection/pathology , Aorta, Thoracic/pathology , Aortic Aneurysm, Thoracic/ethnology , Aortic Aneurysm, Thoracic/pathology , Asian People , Child , Exons , Female , Fibrillin-1 , Fibrillins , Gene Expression , Genetic Association Studies , HEK293 Cells , Humans , Male , Middle Aged , Mutation , Pedigree , Protein Serine-Threonine Kinases/genetics , Protein Structure, Tertiary , Receptor, Transforming Growth Factor-beta Type I , Receptor, Transforming Growth Factor-beta Type II , Receptors, Transforming Growth Factor beta/genetics , Transfection
17.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 34(6): 487-91, 2009 Jun.
Article Zh | MEDLINE | ID: mdl-19587429

OBJECTIVE: To characterize the hemodynamic changes of chronic congestive heart failure(CHF) model induced by rapid right ventricular pacing after myocardial infarction in awake Beagle dogs. METHODS: Five healthy adult male Beagle dogs were prepared for surgery. After the probes for measurement and the pacing leads were implanted, the left anterior descending artery was ligated during the surgery to induce myocardial infarction in the anterior wall of the left ventricle close to the apex. Six weeks after the surgery, rapid right ventricular pacing was initiated at the rate of 220 to 260 beats per minute for 4 weeks to induce CHF. Echocardiography was performed before the surgery. Both echocardiography and hemodynamic measurement were carried out before the rapid pacing and 4 weeks after the rapid pacing when the Beagle dogs were awake. RESULTS: There was no significant difference in left ventricle end diastolic diameter (LVEDD), left ventricle ejective fraction (LVEF), and fractional shortening (FS) between pre-operation and pre-pacing. LVEDD [(44.71+/-3.35) vs. (38.01+/-1.54) mm] and left ventricle end diastolic pressure (LVEDP) [(25.63+/-1.86) vs. (10.58+/-1.23) mmHg] at 4 weeks after pacing significantly increased compared with the pre-pacing data(P<0.05). LVEF, FS, and LV dp/dt max were significantly declined (P<0.01). CONCLUSION: Left ventricle remodeling and hemodynamic changes in the Beagle dog CHF models produced by rapid right ventricular pacing after myocardial infarction are similar to the changes observed in CHF of human beings.


Disease Models, Animal , Heart Failure , Hemodynamics/physiology , Animals , Dogs , Heart Failure/physiopathology , Male
18.
J Biomed Mater Res A ; 82(1): 139-44, 2007 Jul.
Article En | MEDLINE | ID: mdl-17269141

The clinical benefits of coronary artery bypass graft operations can be compromised by postoperative vasospasm. Traditionally, local papaverine (PPV) has been employed during the procedure to prevent and counteract vasospasm. But the relatively short action period limited its application. Fibrin glue (FG) might be a potential carrier of PPV for counteracting vasospasm in a longer action period than PPV solution. After FG incorporated with PPV (PPV-FG) was locally administrated in axillary and femoral arteries of dogs, PPV concentrations in artery vessels surrounding the administration sites were compared with the concentrations at the same sites in dogs given PPV solution. The properties of PPV's release in vitro and maintenance in vessel as well as the influence on the mean peripheral blood pressure and drug concentration in peripheral vein after the introduction PPV-FG on the surface of artery in dogs were evaluated. FG was considered to provide a sustained release of PPV and could maintain a high PPV concentration in artery vessel around the administration site. The results suggested that FG was an effective substrate for reserving PPV in the administrated site in a defined period.


Biocompatible Materials , Drug Delivery Systems , Fibrin Tissue Adhesive , Vasodilator Agents/administration & dosage , Animals , Blood Vessel Prosthesis , Coronary Artery Bypass/adverse effects , Coronary Vasospasm/prevention & control , Delayed-Action Preparations , Dogs , Female , Femoral Artery/transplantation , Humans , In Vitro Techniques , Male , Materials Testing , Papaverine/administration & dosage
19.
Zhonghua Wai Ke Za Zhi ; 44(22): 1532-4, 2006 Nov 15.
Article Zh | MEDLINE | ID: mdl-17359656

OBJECTIVE: To study the risk factors of acute renal insufficiency (ARI) following coronary artery bypass grafting (CABG). METHODS: The clinic data of 2242 patients undertaking CABG between July 1997 and July 2006 were retrospectively analyzed, and ARI following CABG was included. RESULTS: ARI occurred in 219 patients, with an incidence of 9.8%. Univariate analysis revealed that advanced age, diabetes mellitus, preoperative chronic renal dysfunction, left main disease, low left ventricular erection faction, emergency operation, on-pump CABG, ascending aortic atherosclerosis, postoperative respiratory function insufficiency and low cardiac output syndrome were significantly related to ARI following CABG, and logistic multivariate regression analysis showed that presence of advanced age (P = 0.031), preoperatively chronic renal dysfunction (CrCl or= 150 micromol/L, P = 0.041), on-pump CABG (P < 0.001), postoperative respiratory function insufficiency (P = 0.013) and low cardiac output syndrome (P = 0.004) were independent risk factors of ARI. CONCLUSIONS: Advanced age, preoperatively chronic renal dysfunction, on-pump CABG, postoperative respiratory function insufficiency and low cardiac output syndrome are the risk factors of ARI following CABG.


Acute Kidney Injury/etiology , Coronary Artery Bypass/adverse effects , Acute Kidney Injury/epidemiology , China/epidemiology , Female , Humans , Incidence , Male , Middle Aged , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Retrospective Studies , Risk Factors
20.
Zhonghua Wai Ke Za Zhi ; 41(8): 597-9, 2003 Aug.
Article Zh | MEDLINE | ID: mdl-14505534

OBJECTIVE: The increasing number of aged patients with severe ascending aorta atherosclerosis who are undergoing coronary artery bypass graft (CABG) present high risk for ascending aortic cannulation, cross-clamping or partial occluding and proximal anastomosis. We reviewed the surgical experience in 22 patients of CABG with ascending aorta atherosclerosis and tried to find the way to minimize the complications. METHODS: Twenty-two patients with severe atherosclerotic and calcified ascending aorta underwent CABG in our hospital. Thirteen of them received CABG on beating heart. Nine patients had their CABG with extracorporeal circulation. With deep hypothermia, we reduced the flow rate and intermittently arrested the circulation for the proximal anastomosis on ascending aorta in 5 patients with neither cross-clamping nor partial occluding. The sequential grafts and "Y" type anastomosis between reversed saphenous venous grafts were employed. RESULTS: Twenty of the patients survived after surgery. One died of inhalation pneumonia in two weeks after surgery. Another died of right hemothorax in ten days after surgery. The complications include: pneumonia 4 patients (18%), angina 2 patients (9%), ventricular fibrillation 1 patients (5%), post-CABG myocardium infarction 1 case (5%) and hemothorax 1 case (5%). There is no neurologic complications or aortic dissection after CABG. CONCLUSION: CABG on beating heart with pedicel arterial grafts is the best approach to performing the surgery without touching the diseased ascending aorta. Ventricular fibrillation under mild hypothermia cardiopulmonary bypass and left ventricular suction were employed for quiet and bloodless field while distal anastomosis had no cross-clamping the ascending aorta. Also deep hypothermia and intermittently circulatory arrest offer quiet and bloodless field for the proximal anastomosis on ascending aorta without cross-clamping or partial-occluding. Distal sequential anastomosis and proximal "Y" type anastomosis are the effective approach to minimizing the proximal anastomosis on the ascending aorta.


Aortic Diseases/surgery , Atherosclerosis/surgery , Coronary Artery Bypass/methods , Aged , Aged, 80 and over , Aortic Diseases/complications , Atherosclerosis/complications , Coronary Artery Disease/complications , Coronary Artery Disease/surgery , Female , Humans , Male , Retrospective Studies , Treatment Outcome
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