Simultaneous pectoralis major-latissimus dorsi myocutaneous flap: An option of reconstruction for open sternal wounds

SummaryManagement of the open sternal wound after surgery is a challenge. We report a retrospective series of cases with regard to the management of sternal wounds according to our own experience and a review of the related literature. A retrospective chart review from June 2007 to February 2010 of patients with infective and open sternal wounds after surgery was performed. There were seven patients with a previous history of type A aortic dissection treated with the Bentall operation, thymoma with excision, mitral and tricuspid regurgitation with double valve replacement, and acute myocardial infarction with a ventricular-assist device or coronary artery bypass graft. All wound cultures of the seven patients showed positive findings. All patients received the latissimus dorsi (LD) myocutaneous flap for lower sternal wound reconstruction under the decubitus position and a contralateral pedicled rotated pectoralis major (PM) myocutaneous flap for the upper sternal wound. The residual wound was covered with a split-thickness skin graft. The mean age of the seven patients, including four males and three females, was 58.1 years (range: 33–73 years). The mean follow-up was 37.7 months (range: 30–44 months). The average time span between the final débridement and the flap reconstruction procedure was 5.2 ± 1.8 days. The harvested area of LD myocutaneous flap ranged from 25 × 10 cm2 to 15 × 8 cm2, and the area of PM myocutaneous flap ranged from 15×15 cm2 to 10 × 5 cm2. Four of seven patients had an omental flap initially, but salvage surgery was performed using a simultaneous pectoralis major-LD flap. Three cases underwent simultaneous PM-LD flap directly. One patient expired on postoperative Day 4 because of sudden ventricular fibrillation, but no postoperative complications were noted in the other six patients. With long-term follow-up, all patients survived without significant complications. The simultaneous PM-LD myocutaneous flap is a reliable option for open sternal wound reconstruction

Using the CVP Traffic Detection Model at Road-Section Applies to Traffic Information Collection and Monitor - the Case Study

This paper proposes a using Cellular-Based Vehicle Probe (CVP) at road-section (RS) method to detect and setup a model for traffic flow information (info) collection and monitor. There are multiple traffic collection devices including CVP, ETC-Based Vehicle Probe (EVP), Vehicle Detector (VD), and CCTV as traffic resources to serve as road condition info for predicting the traffic jam problem, monitor and control. The main project has been applied at Tai # 2 Ghee-Jing roadway connects to Wan-Li section as a trial field on fiscal year of 2017-2018. This paper proposes a man-flow turning into traffic-flow with Long-Short Time Memory (LTSM) from recurrent neural network (RNN) model. We also provide a model verification and validation methodology with RNN for cross verification of system performance

Rationalization and Design of the Complementarity Determining Region Sequences in an Antibody-Antigen Recognition Interface

Protein-protein interactions are critical determinants in biological systems. Engineered proteins binding to specific areas on protein surfaces could lead to therapeutics or diagnostics for treating diseases in humans. But designing epitope-specific protein-protein interactions with computational atomistic interaction free energy remains a difficult challenge. Here we show that, with the antibody-VEGF (vascular endothelial growth factor) interaction as a model system, the experimentally observed amino acid preferences in the antibody-antigen interface can be rationalized with 3-dimensional distributions of interacting atoms derived from the database of protein structures. Machine learning models established on the rationalization can be generalized to design amino acid preferences in antibody-antigen interfaces, for which the experimental validations are tractable with current high throughput synthetic antibody display technologies. Leave-one-out cross validation on the benchmark system yielded the accuracy, precision, recall (sensitivity) and specificity of the overall binary predictions to be 0.69, 0.45, 0.63, and 0.71 respectively, and the overall Matthews correlation coefficient of the 20 amino acid types in the 24 interface CDR positions was 0.312. The structure-based computational antibody design methodology was further tested with other antibodies binding to VEGF. The results indicate that the methodology could provide alternatives to the current antibody technologies based on animal immune systems in engineering therapeutic and diagnostic antibodies against predetermined antigen epitopes

Protein-Protein Interaction Site Predictions with Three-Dimensional Probability Distributions of Interacting Atoms on Protein Surfaces

Protein-protein interactions are key to many biological processes. Computational methodologies devised to predict protein-protein interaction (PPI) sites on protein surfaces are important tools in providing insights into the biological functions of proteins and in developing therapeutics targeting the protein-protein interaction sites. One of the general features of PPI sites is that the core regions from the two interacting protein surfaces are complementary to each other, similar to the interior of proteins in packing density and in the physicochemical nature of the amino acid composition. In this work, we simulated the physicochemical complementarities by constructing three-dimensional probability density maps of non-covalent interacting atoms on the protein surfaces. The interacting probabilities were derived from the interior of known structures. Machine learning algorithms were applied to learn the characteristic patterns of the probability density maps specific to the PPI sites. The trained predictors for PPI sites were cross-validated with the training cases (consisting of 432 proteins) and were tested on an independent dataset (consisting of 142 proteins). The residue-based Matthews correlation coefficient for the independent test set was 0.423; the accuracy, precision, sensitivity, specificity were 0.753, 0.519, 0.677, and 0.779 respectively. The benchmark results indicate that the optimized machine learning models are among the best predictors in identifying PPI sites on protein surfaces. In particular, the PPI site prediction accuracy increases with increasing size of the PPI site and with increasing hydrophobicity in amino acid composition of the PPI interface; the core interface regions are more likely to be recognized with high prediction confidence. The results indicate that the physicochemical complementarity patterns on protein surfaces are important determinants in PPIs, and a substantial portion of the PPI sites can be predicted correctly with the physicochemical complementarity features based on the non-covalent interaction data derived from protein interiors

Multi-ancestry genome-wide association meta-analysis of Parkinson?s disease

Although over 90 independent risk variants have been identified for Parkinson’s disease using genome-wide association studies, most studies have been performed in just one population at a time. Here we performed a large-scale multi-ancestry meta-analysis of Parkinson’s disease with 49,049 cases, 18,785 proxy cases and 2,458,063 controls including individuals of European, East Asian, Latin American and African ancestry. In a meta-analysis, we identified 78 independent genome-wide significant loci, including 12 potentially novel loci (MTF2, PIK3CA, ADD1, SYBU, IRS2, USP8, PIGL, FASN, MYLK2, USP25, EP300 and PPP6R2) and fine-mapped 6 putative causal variants at 6 known PD loci. By combining our results with publicly available eQTL data, we identified 25 putative risk genes in these novel loci whose expression is associated with PD risk. This work lays the groundwork for future efforts aimed at identifying PD loci in non-European populations

Vehicle Collision Prediction under Reduced Visibility Conditions

Rear-end collisions often cause serious traffic accidents. Conventionally, in intelligent transportation systems (ITS), radar collision warning methods are highly accurate in determining the inter-vehicle distance via detecting the rear-end of a vehicle; however, in poor weather conditions such as fog, rain, or snow, the accuracy is significantly affected. In recent years, the advent of Vehicle to Vehicle (V2V) and Vehicle to Infrastructure (V2I) communication systems has introduced new methods for solving the rear-end collision problem. Nevertheless, there is still much left for improvement. For instance, weather conditions have an impact on human-related factors such as response time. To address the issue of collision detection under low visibility conditions, we propose a Visibility-based Collision Warning System (ViCoWS) design that includes four models for prediction horizon estimation, velocity prediction, headway distance prediction, and rear-end collision warning. Based on the history of velocity data, future velocity volumes are predicted. Then, the prediction horizon (number of future time slots to consider) is estimated corresponding to different weather conditions. ViCoWs can respond in real-time to weather conditions with correct collision avoidance warnings. Experiment results show that the mean absolute percentage error of our velocity prediction model is less than 11%. For non-congested traffic under heavy fog (very low visibility of 120 m), ViCoWS warns a driver by as much as 4.5 s prior to a possible future collision. If the fog is medium with a low visibility of 160 m, ViCoWs can give warnings by about 2.1 s prior to a possible future collision. In contrast, the Forward Collision Probability Index (FCPI) method gives warnings by only about 0.6 s before a future collision. For congested traffic under low visibility conditions, ViCoWS can warn a driver by about 1.9 s prior to a possible future collision. In this case, the FCPI method gives 1.2 s for the driver to react before collision

infection–induced partial failure of free anterolateral thigh musculocutaneous flap: Case report

Fusarium species, a soil-borne fungi, causes disease in animals and humans, particularly in immunocompromized patients. A 62-year-old male presented with type II diabetes mellitus, diagnosed 4 years ago. He had a motorcycle accident-caused open tibiofibular fracture of the left lower extremity (Gustilo grade IIIb). With open reduction and internal fixation, an anterolateral thigh musculocutaneous flap was harvested for coverage of exposed bone and defect reconstruction. Partial failure of the flap occurred 9 days following reconstruction, and histological examination revealed Fusarium spp. After treatment with antifungal drugs and debridement, we performed a split-thickness skin graft. At 2-year follow-up, the flap was viable with adequate bone union. This is the first reported case of partial flap failure due to a Fusarium spp. infection. Possibility of fungal infections in patients with late-onset flap failure should be noted. Prompt diagnosis and treatment are needed to prevent repeated free-tissue transfer and/or devastating outcomes

The effect of atorvastatin on survival of rat ischemic flap

AbstractManagement of skin avulsion with tissue exposure is a challenge for plastic surgeons. Clinical observations have suggested that longer survival of skin flap prevents further contamination and infection. Less well known is the role of atorvastatin in avulsion skin flap. Therefore, we attempted to determine whether atorvastatin could alleviate avulsion skin flap in a rat model. Twenty male Sprague–Dawley rats were randomized into two groups: the atorvastatin group and the control. Before operation, each rat received an initial blood perfusion scan as baseline data. Then, each rat received an operation of skin flap incision, elevation, and resuturing to the original position under general anesthesia. Another blood perfusion scan was performed on each rat 30 minutes, 4 days, and 7 days postoperatively. On the 7th postoperative day, the necrotic area of skin flap was measured as the skin flap viability. The skin flap tissues at 2.5 and 5cm distal to the skin flap base were collected for histopathological analysis, as well as measurement of vascular endothelial growth factor (VEGF) mRNA expression, and vascular density. Compared with 30 minutes postoperation, there was a significant increase in the ratio of skin flap blood perfusion on the 4th and 7th days postoperation in both control and atorvastatin groups (p<0.05). Compared with the control group, there was a significant decrease in necrotic area, significant increase in ratio of skin flap blood perfusion on postoperation days 4 and 7, and significant increase in vascular density under high field at 2.5cm distal to the base of skin flap in the atorvastatin group (p<0.05). The VEGF121 and VEGF165 mRNA expression at 2.5cm distal to the base of skin flap differed significantly between the two groups (p<0.05). Compared with the control group, atorvastatin treatment improved skin flap blood perfusion, vascular density, and necrotic area dependent on VEGF mRNA expression

Fabrication and strength analysis of humanoid focusing mechanism

The human eye was constructed from the soft lens and the ciliary muscle. The ciliary muscle induces force on the lens through an array of fibrillar structure that surrounds the lens. In this paper, the humanoid focusing mechanism which consists of parylene nanofibers and soft polymer lens was presented and demonstrated. The soft polymer lens was constructed of a PDMS envelope and a silicone core. The parylene nanofrillar film was fabricated by anodic aluminum oxide (AAO) template and used to adhere to the lens and to transfer the accommodation force. For verifying the function of the fibrillar structure around the lens, an experiment stage was set up to test the normal and shear strength and to compare two bonding conditions: fibrillar bonding and plate bonding. Besides, the relation between the focal length and applied force was estimated by the lens contour measurement and the laser light focusing measurement