Search

The ubiquitination pathway regulates growth, development, and stress responses in plants, and the U-box protein family of ubiquitin ligases has important roles in this pathway. Here, 64 putative U-box proteins were identified in the Medicago truncatula genome. In addition to the conserved U-box motif, other functional domains, such as the ARM, kinase, KAP, and WD40 domains, were also detected. Phylogenetic analysis of the M. truncatula U-box proteins grouped them into six subfamilies, and chromosomal mapping and synteny analyses indicated that tandem and segmental duplications may have contributed to the expansion and evolution of the U-box gene family in this species. Using RNA-seq data from M. truncatula seedlings subjected to three different abiotic stresses, we identified 33 stress-inducible plant U-box genes (MtPUBs). Specifically, 25 salinity-, 15 drought-, and 16 cold-regulated MtPUBs were detected. Among them, MtPUB10, MtPUB17, MtPUB18, MtPUB35, MtPUB42, and MtPUB44 responded to all three stress conditions. Expression profiling by qRT-PCR was consistent with the RNA-seq data, and stress-related elements were identified in the promoter regions. The present findings strongly indicate that U-box proteins play critical roles in abiotic stress response in M. truncatula. [ABSTRACT FROM AUTHOR]

Although bipolar electrograms (Bi-egms) are commonly used for catheter mapping and ablation of cardiac arrhythmias, the accuracy and reproducibility of Bi-egms have not been evaluated. We aimed to clarify the influence of the catheter orientation (CO), catheter contact angle (CA), local conduction velocity (CV), scar size, and catheter type on the Bi-egm morphology using an in silico 3-dimensional realistic model of atrial fibrillation. We constructed a 3-dimensional, realistic, in silico left atrial model with activation wave propagation including bipolar catheter models. Bi-egms were obtained by computing the extracellular potentials from the distal and proximal electrodes. The amplitude and width were measured on virtual Bi-egms obtained under different conditions created by changing the CO according to the wave direction, catheter-atrial wall CA, local CV, size of the non-conductive area, and catheter type. Bipolar voltages were also compared between virtual and clinically acquired Bi-egms. Bi-egm amplitudes were lower for a perpendicular than parallel CO relative to the wave direction (p<0.001), lower for a 90° than 0° CA (p<0.001), and lower for a CV of 0.13m/s than 0.48m/s (p<0.001). Larger sized non-conductive areas were associated with a decreased bipolar amplitude (p<0.001) and increased bipolar width (p<0.001). Among three commercially available catheters (Orion, Pentaray, and Thermocool), those with more narrowly spaced and smaller electrodes produced higher voltages on the virtual Bi-egms (p<0.001). Multiple factors including the CO, CA, CV, and catheter design significantly influence the Bi-egm morphology. Universal voltage cut-off values may not be appropriate for bipolar voltage-guided substrate mapping. [ABSTRACT FROM AUTHOR]

Neurotensin is a peptide hormone released from enteroendocrine cells in the small intestine in response to fat ingestion. Although the mechanisms regulating neurotensin secretion are still incompletely understood, our recent findings implicate a role for extracellular signal–regulated kinase 1 and 2 as positive regulators of free fatty acid-stimulated neurotensin secretion. Previous studies have shown that kinase suppressor of Ras 1 acts as a molecular scaffold of the Raf/MEK/extracellular signal–regulated kinase 1 and 2 kinase cascade and regulates intensity and duration of extracellular signal–regulated kinase 1 and 2 signaling. Here, we demonstrate that inhibition of kinase suppressor of Ras 1 attenuates neurotensin secretion and extracellular signal–regulated kinase 1 and 2 signaling in human endocrine cells. Conversely, we show that overexpression of kinase suppressor of Ras 1 enhances neurotensin secretion and extracellular signal–regulated kinase 1 and 2 signaling. We also show that inhibition of extracellular signal–regulated kinase 2 and exocyst complex component 70, a substrate of extracellular signal–regulated kinase 2 and mediator of secretory vesicle exocytosis, potently inhibits basal and docosahexaenoic acid-stimulated neurotensin secretion, whereas overexpression of exocyst complex component 70 enhances basal and docosahexaenoic acid-stimulated neurotensin secretion. Together, our findings demonstrate a role for kinase suppressor of Ras 1 as a positive regulator of neurotensin secretion from human endocrine cells and indicate that this effect is mediated by the extracellular signal–regulated kinase 1 and 2 signaling pathway. Moreover, we reveal a novel role for exocyst complex component 70 in regulation of neurotensin vesicle exocytosis through its interaction with the extracellular signal–regulated kinase 1 and 2 signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Although hypoalbuminemia is a known risk factor for acute kidney injury (AKI) following surgery, little is known about its effects following aneurysm clipping surgery. We aimed to investigate the predictors of AKI and overall mortality and assessed the relationship between preoperative albumin and postoperative outcomes after aneurysm clipping surgery. Methods: This study included 2,339 patients who underwent aneurysm clipping surgery. According to the criteria updated by the Kidney Disease: Improving Global Outcomes (KDIGO), patients were classified into AKI and no AKI group. Independent AKI predictors were analyzed by multivariate methods, and the influence of AKI on the outcome variables was assessed with by propensity score matching analysis. Survival in relation to AKI was analyzed using the Kaplan–Meier method. Results: The total proportion of patients who developed AKI was 1.9%. The cutoff value of preoperative albumin for predicting AKI was 3.9 g/dL. Multivariate analyses showed that preoperative albumin≤ 3.9 g/dL, aneurysmal subarachnoid hemorrhage, male sex, phenylephrine use, and hemoglobin were associated with postoperative AKI development. In multivariate analysis, mortality was increased in AKI patients (p< 0.01). After propensity score matching, preoperative albumin≤ 3.9 g/dL was significantly related to AKI and overall mortality. Conclusion: Preoperative albumin≤ 3.9 g/dL is associated with postoperative AKI and mortality. [ABSTRACT FROM AUTHOR]

Laparoscopic pylorus-preserving pancreaticoduodenectomy is being performed more frequently because of improved surgical techniques. Although several studies have demonstrated safety and favourable outcomes of laparoscopic pylorus-preserving pancreaticoduodenectomy compared to open pylorus-preserving pancreaticoduodenectomy, few studies have focused on the development of postoperative acute kidney injury. This retrospective study compared the prevalence and risk factors of acute kidney injury following laparoscopic and open pylorus-preserving pancreaticoduodenectomy. Data from 809 patients who underwent pylorus-preserving pancreaticoduodenectomy between February 2012 and September 2016 were analysed. Patients were divided into two groups according to the surgical procedure (open pylorus-preserving pancreaticoduodenectomy [n = 632] vs laparoscopic pylorus-preserving pancreaticoduodenectomy [n = 177]). The Kidney Disease: Improving Global Outcomes criteria were used to define postoperative acute kidney injury and risk factors were investigated using multivariable logistic regression analysis with propensity score matching analysis and standardized mortality ratio weighting to compare outcomes. No significant differences were found in the occurrence of postoperative acute kidney injury and incidence of postoperative ICU admission between open and laparoscopic pylorus-preserving pancreaticoduodenectomy groups after propensity score matching (p = 1.000, p = 0.999, respectivelyand standardized mortality ratio weighted analysis (p = 0.619, p = 0.982, respectively). Hospital stay was significantly shorter in the laparoscopic pylorus-preserving pancreaticoduodenectomy group (propensity matched set, mean [SD], 16.7 [10.0] vs. 18.7 [9.6] days, p = 0.004; standardized mortality ratio, 16.6 [9.9] vs. 18.1 [8.8] days, p = 0.001). There was no significant difference in postoperative acute kidney injury incidence between both groups. Laparoscopic pylorus-preserving pancreaticoduodenectomy is promising with comparable postoperative outcomes to open pylorus-preserving pancreaticoduodenectomy and has the advantage of shorter hospital stay. [ABSTRACT FROM AUTHOR]

Background: We previously reported that stable rotors are observed in in-silico human atrial fibrillation (AF) models, and are well represented by a dominant frequency (DF). In the current study, we hypothesized that the outcome of DF ablation is affected by conduction velocity (CV) conditions and examined this hypothesis using in-silico 3D-AF modeling. Methods: We integrated 3D CT images of left atrium obtained from 10 patients with persistent AF (80% male, 61.8±13.5 years old) into in-silico AF model. We compared AF maintenance durations (max 300s), spatiotemporal stabilities of DF, phase singularity (PS) number, life-span of PS, and AF termination or defragmentation rates after virtual DF ablation with 5 different CV conditions (0.2, 0.3, 0.4, 0.5, and 0.6m/s). Results: 1. AF maintenance duration (p<0.001), spatiotemporal mean variance of DF (p<0.001), and the number of PS (p = 0.023) showed CV dependent bimodal patterns (highest at CV0.4m/s and lowest at CV0.6m/s) consistently. 2. After 10% highest DF ablation, AF defragmentation rates were the lowest at CV0.4m/s (37.8%), but highest at CV0.5 and 0.6m/s (all 100%, p<0.001). 3. In the episodes with AF termination or defragmentation followed by 10% highest DF ablation, baseline AF maintenance duration was shorter (p<0.001), spatiotemporal mean variance of DF was lower (p = 0.014), and the number of PS was lower (p = 0.004) than those with failed AF defragmentation after DF ablation. Conclusion: Virtual ablation of DF, which may indicate AF driver, was more likely to terminate or defragment AF with spatiotemporally stable DF, but not likely to do so in long-lasting and sustained AF conditions, depending on CV. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of four strains, generally used in clinic, including Bifidobacterium longum, Lactobacillus acidophilus, Streptococcus thermophilus and Enterococcus faecalis, and their related products on human colonic smooth muscle in vitro. Methods: Human colonic circular muscle strips obtained from disease-free margins of resected segments from 25 patients with colorectal cancer were isometrically examined in a constant-temperature organ bath and exposed to different concentrations of living bacteria, sonicated cell fractions and cell-free supernatant (CFS). The area under the curve (AUC) representing the contractility of smooth muscle strips was calculated. Results: (1) The four living probiotics inhibited the contractility of human colonic muscle strips only at high concentration (1010 CFUs/mL, all P<0.05). (2) The sonicated cell fractions from the four probiotics obviously inhibited human colonic smooth muscle strips in a dose-dependent manner (P<0.01). (3) The CFS from the four probiotics also inhibited colonic smooth muscle strips in a dose-dependent manner (all P<0.05). (4) The inhibition effect of CFS from Streptococcus thermophilus and Enterococcus faecalis decreased obviously when pretreated with NG-nitro-L-arginine (L-NNA, 10−5 mol/L) (P<0.05), but not the Bifidobacterium longum and Lactobacillus acidophilus (P>0.05). Conclusion: Four common probiotics related products, including the sonicated cell fractions and the CFS, obviously inhibited human colonic smooth muscles strips contraction in a dose-dependent manner. Only high concentration living probiotics (1010 CFUs/mL) can inhibit the colonic smooth muscles strips contraction. The NO pathway may be partly involved in the inhibitory effect of CFS from Streptococcus thermophilus and Enterococcus faecalis. [ABSTRACT FROM AUTHOR]

New architectures of multilayer artificial neural networks and new methods for training them are rapidly revolutionizing the application of machine learning in diverse fields, including business, social science, physical sciences, and biology. Interpreting deep neural networks, however, currently remains elusive, and a critical challenge lies in understanding which meaningful features a network is actually learning. We present a general method for interpreting deep neural networks and extracting network-learned features from input data. We describe our algorithm in the context of biological sequence analysis. Our approach, based on ideas from statistical physics, samples from the maximum entropy distribution over possible sequences, anchored at an input sequence and subject to constraints implied by the empirical function learned by a network. Using our framework, we demonstrate that local transcription factor binding motifs can be identified from a network trained on ChIP-seq data and that nucleosome positioning signals are indeed learned by a network trained on chemical cleavage nucleosome maps. Imposing a further constraint on the maximum entropy distribution also allows us to probe whether a network is learning global sequence features, such as the high GC content in nucleosome-rich regions. This work thus provides valuable mathematical tools for interpreting and extracting learned features from feed-forward neural networks. [ABSTRACT FROM AUTHOR]

The inflammatory response has been shown to be a major contributor to acute kidney injury. Considering that laparoscopic surgery is beneficial in reducing the inflammatory response, we compared the incidence of postoperative acute kidney injury between laparoscopic liver resection and open liver resection. Among 1173 patients who underwent liver resection surgery, 222 of 926 patients who underwent open liver resection were matched with 222 of 247 patients who underwent laparoscopic liver resection, by using propensity score analysis. The incidence of postoperative acute kidney injury assessed according to the creatinine criteria of the Kidney Disease: Improving Global Outcomes definition was compared between those 1:1 matched groups. A total 77 (6.6%) cases of postoperative acute kidney injury occurred. Before matching, the incidence of acute kidney injury after laparoscopic liver resection was significantly lower than that after open liver resection [1.6% (4/247) vs. 7.9% (73/926), P < 0.001]. After 1:1 matching, the incidence of postoperative acute kidney injury was still significantly lower after laparoscopic liver resection than after open liver resection [1.8% (4/222) vs. 6.3% (14/222), P = 0.008; odds ratio 0.273, 95% confidence interval 0.088–0.842, P = 0.024]. The postoperative inflammatory marker was also lower in laparoscopic liver resection than in open liver resection in matched set data (white blood cell count 12.7 ± 4.0 × 103/μL vs. 14.9 ± 3.9 × 103/μL, P < 0.001). Our findings suggest that the laparoscopic technique, by decreasing the inflammatory response, may reduce the occurrence of postoperative acute kidney injury during liver resection surgery. [ABSTRACT FROM AUTHOR]

Background/Aims: Atrial anatomy and thickness may affect the electrical wave-dynamics of atrial fibrillation (AF). We explored the relationship between left atrial (LA) wall thickness (LAWT) or LA geometry and AF wave-dynamics. Methods: We included 15 patients with persistent AF (age, 62.3 ± 11.9 years) who underwent AF catheter ablation. We measured the LAWT, LA endocardial curvature, and SD-curvature (surface bumpiness) from preprocedural computed tomography images. We compared those anatomical characteristics with electrophysiologic parameters such as dominant frequency (DF), Shannon entropy (ShEn), or complex fractionated atrial electrogram (CFAE)-cycle length (CL), calculated from intracardiac bipolar electrograms (300–500 points, 5 s), acquired during ablation procedures. Results: 1. LAWT (excluding fat) varied widely among patients, locations, and types of AF. LAWT was inversely correlated with LA volume (r = -0.565, p = 0.028) and positively correlated with SD-curvature (r = 0.272, p < 0.001). 2. LAWT was positively correlated with ShEn (r = 0.233, p < 0.001) and negatively correlated with CFAE-CL (r = -0.107, p = 0.038). 3. In the multivariate linear regression analyses for AF wave-dynamics parameters, DF (β = -0.29 [95% CI -0.44–-0.14], p < 0.001), ShEn (β = 0.19 [95% CI 0.12–0.25], p < 0.001), and CFAE-CL (β = 7.49 [95% CI 0.65–14.34], p = 0.032) were independently associated with LAWT. Conclusion: Regional LAWT is associated with LA structural features, and has significant correlations with the wave-dynamics parameters associated with electrical wavebreaks or rotors in patients with persistent AF. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this retrospective study is to evaluate the diagnostic value of contrast enhanced sonography plus gastric distention sonography, the Double Contrast-enhanced Ultrasound (DCUS) in gastric lesions. Methods: 107 cases with pathology confirmed gastric lesions were retrospectively reviewed, DCUS and oral contrast agent ultrasound (US) were performed in all cases prior to operation. Perfusion parameters including arrival time (AT), peak intensity (PI), time to peak (TTP), and area under the curve (AUC) of the lesion and surrounding normal tissue were analyzed. A reader blinded to pathology results were asked to rate and compare each case with surgical or resection biopsy pathology results. Results: From the 107 gastric lesions, 75 were malignant gastric lesions (33 gastric cancers,42 gastrointestinal stromal tumors (GISTs)) and 32 were benign gastric lesions (11 inflammatory masses and 21 polypoid adenomas). Compared with US, DCUS achieved higher value in sensitivity (90.6% vs. 70.6%), specificity (75% vs. 62.5%), positive predictive value (89.5% vs. 81.5%), negative predictive value (77.4% vs. 47.6%), and overall accuracy (85.9% vs. 68.2%). When US was tested against DCUS, the increase in correct diagnoses value was significant (P = .01). Furthermore, gastric cancer had faster AT, higher PI and AUC than normal tissue (P<0.05); GIST and Inflammatory mass had higher PI than normal tissue (P<0.05); gastric cancer and GIST had faster AT than polypoid adenoma (P<0.05), Inflammatory mass showed higher PI than other 3 lesions and gastric cancer had higher PI than polypoid adenoma and GIST (P<0.05); gastric cancer and inflammatory mass had larger AUC than polypoid adenoma and GIST (P<0.05). Conclusion DCUS improved diagnostic performance compared with US. The combination of different CEUS enhancement characteristics with quantitative perfusion parameters may provide a promising tool to help differentiate gastric cancer and GIST from benign lesions. [ABSTRACT FROM AUTHOR]

Recent studies suggested that gut microbiota was involved in the development of coronary artery disease. However, the changes of gut microbiota following acute myocardial infarction (AMI) remain unknown. In this study, a total of 66 male Wistar rats were randomly divided into control, AMI and SHAM groups. The controls (n = 6) were sacrificed after anesthesia. The AMI model was built by ligation of left anterior descending coronary artery. The rats of AMI and SHAM groups were sacrificed at 12 h, 1 d, 3 d, 7 d and 14 d post-operation respectively. Gut microbiota was analyzed by 16S rDNA high throughput sequencing. The gut barrier injuries were evaluated through histopathology, transmission electron microscope and immunohistochemical staining. The richness of gut microbiota was significantly higher in AMI group than SHAM group at 7 d after AMI (P<0.05). Principal coordinate analysis with unweighted UniFrac distances revealed microbial differences between AMI and SHAM groups at 7 d. The gut barrier impairment was also the most significant at 7 d post-AMI. We further identified the differences of microorganisms between AMI and SHAM group at 7 d. The abundance of Synergistetes phylum, Spirochaetes phylum, Lachnospiraceae family, Syntrophomonadaceae family and Tissierella Soehngenia genus was higher in AMI group compared with SHAM group at 7 d post-operation (q<0.05). Our study showed the changes of gut microbiota at day 7 post AMI which was paralleled with intestinal barrier impairment. We also identified the microbial organisms that contribute most. [ABSTRACT FROM AUTHOR]

Background: The role of the autonomic nervous system (ANS) on atrial fibrillation (AF) is difficult to demonstrate in the intact human left atrium (LA) due to technical limitations of the current electrophysiological mapping technique. We examined the effects of the ANS on the initiation and maintenance of AF by employing a realistic in silico human left atrium (LA) model integrated with a model of ganglionated plexi (GPs). Methods: We incorporated the morphology of the GP and parasympathetic nerves in a three-dimensional (3D) realistic LA model. For the model of ionic currents, we used a human atrial model. GPs were stimulated by increasing the IK[ACh], and sympathetic nerve stimulation was conducted through a homogeneous increase in the ICa-L. ANS-induced wave-dynamics changes were evaluated in a model that integrated a patient’s LA geometry, and we repeated simulation studies using LA geometries from 10 different patients. Results: The two-dimensional model of pulmonary vein (PV) cells exhibited late phase 3 early afterdepolarization-like activity under 0.05μM acetylcholine (ACh) stimulation. In the 3D simulation model, PV tachycardia was induced, which degenerated to AF via GP (0.05μM ACh) and sympathetic (7.0×ICa-L) stimulations. Under sustained AF, local reentries were observed at the LA-PV junction. We also observed that GP stimulation reduced the complex fractionated atrial electrogram (CFAE)-cycle length (CL, p<0.01) and the life span of phase singularities (p<0.01). GP stimulation also increased the overlap area of the GP and CFAE areas (CFAE-CL≤120ms, p<0.01). When 3 patterns of virtual ablations were applied to the 3D AF models, circumferential PV isolation including the GP was the most effective in terminating AF. Conclusion: Cardiac ANS stimulations demonstrated triggered activity, automaticity, and local reentries at the LA-PV junction, as well as co-localized GP and CFAE areas in the 3D in silico GP model of the LA. [ABSTRACT FROM AUTHOR]

Although recent studies have demonstrated the anti-tumor effects of garlic extract (GE), the exact molecular mechanism is still unclear. In this study, we investigated the molecular mechanism associated with the inhibitory action of GE against bladder cancer EJ cell responses. Treatment with GE significantly inhibited proliferation of EJ cells dose-dependently through G2/M-phase cell cycle arrest. This G2/M-phase cell cycle arrest by GE was due to the activation of ATM and CHK2, which appears to inhibit phosphorylation of Cdc25C (Ser216) and Cdc2 (Thr14/Tyr15), this in turn was accompanied by down-regulation of cyclin B1 and up-regulation of p21WAF1. Furthermore, GE treatment was also found to induce phosphorylation of MAPK (ERK1/2, p38MAPK, and JNK) and AKT. In addition, GE impeded the migration and invasion of EJ cells via inhibition of MMP-9 expression followed by decreased binding activities of AP-1, Sp-1, and NF-κB motifs. Based on microarray datasets, we selected Heat shock protein A6 (HSPA6) as the most up-regulated gene responsible for the inhibitory effects of GE. Interestingly, overexpression of HSPA6 gene resulted in an augmentation effect with GE inhibiting proliferation, migration, and invasion of EJ cells. The augmentation effect of HSPA6 was verified by enhancing the induction of G2/M-phase-mediated ATM-CHK2-Cdc25C-p21WAF1-Cdc2 cascade, phosphorylation of MAPK and AKT signaling, and suppression of transcription factor-associated MMP-9 regulation in response to GE in EJ cells. Overall, our novel results indicate that HSPA6 reinforces the GE-mediated inhibitory effects of proliferation, migration, and invasion of EJ cells and may provide a new approach for therapeutic treatment of malignancies. [ABSTRACT FROM AUTHOR]

Background: The point of phase singularity (PS) is considered to represent a spiral wave core or a rotor in cardiac fibrillation. Computational efficiency is important for detection of PS in clinical electrophysiology. We developed a novel algorithm for highly efficient and robust detection of PS. Methods: In contrast to the conventional method, which calculates PS based on the line integral of the phase around a PS point equal to ±2π (the Iyer-Gray method), the proposed algorithm (the location-centric method) looks for the phase discontinuity point at which PS actually occurs. We tested the efficiency and robustness of these two methods in a two-dimensional mathematical model of atrial fibrillation (AF), with and without remodeling of ionic currents. Results: 1. There was a significant association, in terms of the Hausdorff distance (3.30 ± 0.0 mm), between the PS points measured using the Iyer-Gray and location-centric methods, with almost identical PS trajectories generated by the two methods. 2. For the condition of electrical remodeling of AF (0.3 × ICaL), the PS points calculated by the two methods were satisfactorily co-localized (with the Hausdorff distance of 1.64 ± 0.09 mm). 3. The proposed location-centric method was substantially more efficient than the Iyer-Gray method, with a 28.6-fold and 28.2-fold shorter run times for the control and remodeling scenarios, respectively. Conclusion: We propose a new location-centric method for calculating PS, which is robust and more efficient compared with the conventionally used method. [ABSTRACT FROM AUTHOR]

Background: We previously reported that stable rotors were observed in in-silico human atrial fibrillation (AF) models, and were well represented by dominant frequency (DF). We explored the spatiotemporal stability of DF sites in 3D-AF models imported from patient CT images of the left atrium (LA). Methods: We integrated 3-D CT images of the LA obtained from ten patients with persistent AF (male 80%, 61.8 ± 13.5 years old) into an in-silico AF model. After induction, we obtained 6 seconds of AF simulation data for DF analyses in 30 second intervals (T1–T9). The LA was divided into ten sections. Spatiotemporal changes and variations in the temporal consistency of DF were evaluated at each section of the LA. The high DF area was defined as the area with the highest 10% DF. Results: 1. There was no spatial consistency in the high DF distribution at each LA section during T1–T9 except in one patient (p = 0.027). 2. Coefficients of variation for the high DF area were highly different among the ten LA sections (p < 0.001), and they were significantly higher in the four pulmonary vein (PV) areas, the LA appendage, and the peri-mitral area than in the other LA sections (p < 0.001). 3. When we conducted virtual ablation of 10%, 15%, and 20% of the highest DF areas (n = 270 cases), AF was changed to atrial tachycardia (AT) or terminated at a rate of 40%, 57%, and 76%, respectively. Conclusions: Spatiotemporal consistency of the DF area was observed in 10% of AF patients, and high DF areas were temporally variable. Virtual ablation of DF is moderately effective in AF termination and AF changing into AT. [ABSTRACT FROM AUTHOR]

Persistent atrial fibrillation (PeAF) in humans is characterized by shortening of action potential duration (APD) and attenuation of APD rate-adaptation. However, the quantitative influences of particular ionic current alterations on rate-dependent APD changes, and effects on patterns of reentry in atrial tissue, have not been systematically investigated. Using mathematical models of human atrial cells and tissue and performing parameter sensitivity analysis, we evaluated the quantitative contributions to action potential (AP) shortening and APD rate-adaptation of ionic current remodeling seen with PeAF. Ionic remodeling in PeAF was simulated by reducing L-type Ca2+ channel current (ICaL), increasing inward rectifier K+ current (IK1) and modulating five other ionic currents. Parameter sensitivity analysis, which quantified how each ionic current influenced APD in control and PeAF conditions, identified interesting results, including a negative effect of Na+/Ca2+ exchange on APD only in the PeAF condition. At high pacing rate (2 Hz), electrical remodeling in IK1 alone accounts for the APD reduction of PeAF, but at slow pacing rate (0.5 Hz) both electrical remodeling in ICaL alone (-70%) and IK1 alone (+100%) contribute equally to the APD reduction. Furthermore, AP rate-adaptation was affected by IKur in control and by INaCa in the PeAF condition. In a 2D tissue model, a large reduction (-70%) of ICaL becomes a dominant factor leading to a stable spiral wave in PeAF. Our study provides a quantitative and unifying understanding of the roles of ionic current remodeling in determining rate-dependent APD changes at the cellular level and spatial reentry patterns in tissue. [ABSTRACT FROM AUTHOR]

Background: Although rotors have been considered among the drivers of atrial fibrillation (AF), the rotor definition is inconsistent. We evaluated the nature of rotors in 2D and 3D in- silico models of persistent AF (PeAF) by analyzing phase singularity (PS), dominant frequency (DF), Shannon entropy (ShEn), and complex fractionated atrial electrogram cycle length (CFAE-CL) and their ablation. Methods: Mother rotor was spatiotemporally defined as stationary reentries with a meandering tip remaining within half the wavelength and lasting longer than 5 s. We generated 2D- and 3D-maps of the PS, DF, ShEn, and CFAE-CL during AF. The spatial correlations and ablation outcomes targeting each parameter were analyzed. Results: 1. In the 2D PeAF model, we observed a mother rotor that matched relatively well with DF (>9 Hz, 71.0%, p<0.001), ShEn (upper 2.5%, 33.2%, p<0.001), and CFAE-CL (lower 2.5%, 23.7%, p<0.001). 2. The 3D-PeAF model also showed mother rotors that had spatial correlations with DF (>5.5 Hz, 39.7%, p<0.001), ShEn (upper 8.5%, 15.1%, p <0.001), and CFAE (lower 8.5%, 8.0%, p = 0.002). 3. In both the 2D and 3D models, virtual ablation targeting the upper 5% of the DF terminated AF within 20 s, but not the ablations based on long-lasting PS, high ShEn area, or lower CFAE-CL area. Conclusion: Mother rotors were observed in both 2D and 3D human AF models. Rotor locations were well represented by DF, and their virtual ablation altered wave dynamics and terminated AF. [ABSTRACT FROM AUTHOR]

In a vehicular ad hoc network (VANET), the periodic exchange of single-hop status information broadcasts (beacon frames) produces channel loading, which causes channel congestion and induces information conflict problems. To guarantee fairness in beacon transmissions from each node and maximum network connectivity, adjustment of the beacon transmission power is an effective method for reducing and preventing channel congestion. In this study, the primary factors that influence wireless channel loading are selected to construct the KF-BCLF, which is a channel load forecasting algorithm based on a recursive Kalman filter and employs multiple regression equation. By pre-adjusting the transmission power based on the forecasted channel load, the channel load was kept within a predefined range; therefore, channel congestion was prevented. Based on this method, the CLF-BTPC, which is a transmission power control algorithm, is proposed. To verify KF-BCLF algorithm, a traffic survey method that involved the collection of floating car data along a major traffic road in Changchun City is employed. By comparing this forecast with the measured channel loads, the proposed KF-BCLF algorithm was proven to be effective. In addition, the CLF-BTPC algorithm is verified by simulating a section of eight-lane highway and a signal-controlled urban intersection. The results of the two verification process indicate that this distributed CLF-BTPC algorithm can effectively control channel load, prevent channel congestion, and enhance the stability and robustness of wireless beacon transmission in a vehicular network. [ABSTRACT FROM AUTHOR]

Objective: C-peptide has been reported to be a marker of subclinical atherosclerosis in type 2 diabetes mellitus (T2DM) patients, whereas its role in coronary artery disease (CAD) has not been clarified, especially in diabetics with differing body mass indices (BMIs). Design and Methods: This cross-sectional study included 501 patients with T2DM. First, all subjects were divided into the following two groups: CAD and non-CAD. Then, binary logistic regression was used to determine the risk factors for CAD for all patients. To clarify the role of obesity, we re-divided all subjects into two additional groups (obese and non-obese) based on BMI. Finally, binary logistic regression was used to determine the risk factors for CAD for each weight group. Results: The patients with CAD showed a higher BMI and fasting C-peptide level in addition to an increased prevalence of traditional risk factors for CAD, such as hypertension, insulin resistance, higher cholesterol, cysteine-C (Cys-C) and lower estimated glomerular filtration rate (eGFR). Logistic regression analysis showed that fasting C-peptide (OR=1.513, p=0.005), insulin treatment (OR=1.832, p=0.027) hypertension (OR=1.987, p=0.016) and hyperlipidemia (OR=4.159, p<0.001) significantly increased the risk of clinical CAD in the T2DM patients independent of age, gender, diabetes duration, smoking and alcohol statuses, fasting insulin and glucose, hypoglycemic episodes, UA and eGFR. Additionally, in both of the obese (OR=1.488, p=0.049) and non-obese (OR=1.686, p=0.037) DM groups, C-peptide was associated with an increased risk of CAD after multiple adjustments. Conclusions: C-peptide is associated with an increased CAD risk in T2DM patients, no matter whether they are obese or not. [ABSTRACT FROM AUTHOR]

Fruit and seed development in plants is a complex biological process mainly involved in input and biosynthesis of many storage compounds such as proteins and oils. Although the basic biochemical pathways for production of the storage metabolites in plants are well characterized, their regulatory mechanisms are not fully understood. In this study, we functionally identified rapeseed (Brassica napus) miR394 with its target gene Brassica napus LEAF CURLING RESPONSIVENESS (BnLCR) to dissect a role of miR394 during the fruit and seed development. Transgenic rapeseed plants over-expressing miR394 under the control of the cauliflower mosaic virus 35S promoter were generated. miR394 over-expression plants exhibited a delayed flowering time and enlarged size of plants, leaf blade, pods and seed body, but developed seeds with higher contents of protein and glucosinolates (GLS) and lower levels of oil accumulation as compared to wild-type. Over-expression of miR394 altered the fatty acid (FA) composition by increasing several FA species such as C16:0 and C18:0 and unsaturated species of C20:1 and C22:1 but lowering C18:3. This change was accompanied by induction of genes coding for transcription factors of FA synthesis including LEAFY COTYLEDON1 (BnLEC1), BnLEC2, and FUSCA3 (FUS3). Because the phytohormone auxin plays a crucial role in fruit development and seed patterning, the DR5-GUS reporter was used for monitoring the auxin response in Arabidopsis siliques and demonstrated that the DR5 gene was strongly expressed. These results suggest that BnmiR394 is involved in rapeseed fruit and seed development. [ABSTRACT FROM AUTHOR]

Current target enrichment systems for large-scale next-generation sequencing typically require synthetic oligonucleotides used as capture reagents to isolate sequences of interest. The majority of target enrichment reagents are focused on gene coding regions or promoters en masse. Here we introduce development of a customizable targeted capture system using biotinylated RNA probe baits transcribed from sheared bacterial artificial chromosome clone templates that enables capture of large, contiguous blocks of the genome for sequencing applications. This clone adapted template capture hybridization sequencing (CATCH-Seq) procedure can be used to capture both coding and non-coding regions of a gene, and resolve the boundaries of copy number variations within a genomic target site. Furthermore, libraries constructed with methylated adapters prior to solution hybridization also enable targeted bisulfite sequencing. We applied CATCH-Seq to diverse targets ranging in size from 125 kb to 3.5 Mb. Our approach provides a simple and cost effective alternative to other capture platforms because of template-based, enzymatic probe synthesis and the lack of oligonucleotide design costs. Given its similarity in procedure, CATCH-Seq can also be performed in parallel with commercial systems. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether fluctuations between the fasting and 2-h postload glucose ([2-hPBG]-fasting blood glucose [FBG]) states are associated with glomerular hyperfiltration (GHF) in middle-aged and elderly Chinese patients with newly diagnosed diabetes. Design and Methods: In this study, we included 679 newly diagnosed diabetes patients who were ≥40 years old. All the subjects were divided into two groups; those with HbA1c<7% and ≥7%. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was used to estimate the glomerular filtration rate (GFR). GHF was defined as an eGFR ≥ the 90th percentile. First, a multiple linear regression analysis was used to estimate the association of 2-hPBG-FBG with eGFR. Then, a generalized additive model was used to explore the possible nonlinear relationship between 2-hPBG-FBG and eGFR. Next, the 2-hPBG-FBG values were divided into four groups as follows: 0–36, 36–72, 72–108 and ≥108 mg/dl. Finally, a multiple logistic regression analysis was used to investigate the association of 2-hPBG-FBG with the risk of GHF. Results: For the group with HbA1c<7%, the eGFR and the percentage of GHF were significantly higher compared with the group with HbA1c≥7%. After adjusting for age, gender, body mass index (BMI), systolic blood pressure (BP), diastolic BP, fasting insulin, cholesterol, triglycerides, smoking, drinking and glycated hemoglobin (HbA1c), 2-hPBG-FBG was significantly associated with increased eGFR and an increased risk of GHF (the GHF risk increased by 64.9% for every 36.0 mg/dl [2.0 mmol/L] 2-hPBG-FBG increase) only in those patients with HbA1c<7%. Additionally, 2-hPBG-FBG and eGFR showed a nonlinear association (P<0.001). Conclusions: Increased fluctuations between the fasting and 2-h postload glucose states are closely associated with increased eGFR and an increased risk of GHF in newly diagnosed diabetes patients with HbA1c<7%. [ABSTRACT FROM AUTHOR]

Rabbits are commonly used as laboratory animal models to investigate human diseases and phylogenetic development. However, pluripotent stem cells that contribute to germline transmission have yet to be established in rabbits. The transcription factor Oct4, also known as Pou5f1, is considered essential for the maintenance of the pluripotency of stem cells. Hence, pluripotent cells can be identified by monitoring Oct4 expression using a well-established Oct4 promoter-based reporter system. This study developed a rabbit Oct4 promoter-based enhanced green fluorescent protein (EGFP) reporter system by transfecting pROP2-EGFP into rabbit fetal fibroblasts (RFFs). The transgenic RFFs were used as donor cells for somatic cell nuclear transfer (SCNT). The EGFP expression was detected in the blastocysts and genital ridges of SCNT fetuses. Fibroblasts and neural stem cells (NSCs) were derived from the SCNT fetuses. EGFP was also reactivated in blastocysts after the second SCNT, and induced pluripotent stem cells (iPSCs) were obtained after reprogramming using Yamanaka's factors. The results above indicated that a rabbit reporter system used to monitor the differentiating status of cells was successfully developed. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between lipid profiles [including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C)] and a mild decline in the estimated glomerular filtration rate (eGFR) in subjects with normal serum lipid levels. Design and Methods: In this study, we included 2647 participants who were ≥40 years old and had normal serum lipid levels. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was used to estimate the GFR. A mildly reduced eGFR was defined as 60–90 mL/min/1.73 m2. First, multiple linear regression analysis was used to estimate the association of lipid profiles with the eGFR. Then, the levels of each lipid component were divided into four groups, using the 25th, 50th and 75th percentiles as cut-off points. Finally, multiple logistic regression analysis was used to investigate the association of different lipid components with the risk of mildly reduced eGFR. Results: In the group with a mildly reduced eGFR, TG and LDL-C levels were significantly increased, but HDL-C levels were significantly decreased. After adjusting for age, gender, body mass index (BMI), systolic blood pressure (SBP), glycated hemoglobin (HbA1c), smoking and drinking, only TC and TG were independently related to the eGFR. Additionally, only TG showed a linear relationship with an increased risk of a mildly reduced eGFR, with the highest quartile group (TG: 108–150 mg/dl [1.22–1.70 mmol/L]) having a significantly increased risk after adjusting for the above factors. Conclusions: Triglyceride levels are closely associated with a mildly reduced eGFR in subjects with normal serum lipid levels. Dyslipidemia with lower TG levels could be used as new diagnostic criteria for subjects with mildly reduced renal function. [ABSTRACT FROM AUTHOR]

Objective: To investigate how the glucose variability between fasting and a 2-h postload glucose state (2-h postload plasma glucose [2hPG]-fasting plasma glucose [FPG]) is associated with chronic kidney disease (CKD) in middle-aged and elderly Chinese patients previously diagnosed with type 2 diabetes. Design and Methods: This cross-sectional study included 1054 previously diagnosed type 2 diabetes patients who were 40 years of age and older. First, the subjects were divided into two groups based on a glycated hemoglobin (HbA1c) value of 7%. Each group was divided into two subgroups, with or without CKD. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was used to estimate the glomerular filtration rate (GFR). CKD was defined as eGFR<60 mL/min/1.73 m2. Multiple linear regression analysis was used to estimate the association between the 2hPG-FPG and eGFR. The 2hPG-FPG value was divided into four groups increasing in increments of 36 mg/dl (2.0 mmol/L): 0–72, 72–108, 108–144 and ≥144 mg/dl, based on the quartiles of patients with HbA1c levels ≥7%; then, binary logistic regression analysis was used to investigate the association between 2hPG-FPG and the risk of CKD. Results: In the patients with HbA1c levels ≥7%, the 2hPG-FPG was significantly associated with decreased eGFR and an increased risk of CKD independent of age, gender, body mass index (BMI), systolic blood pressure (BP), diastolic BP, smoking, and drinking, as well as fasting insulin, cholesterol, triglyceride, and HbA1c levels. The patients with 2hPG-FPG values ≥144 mg/dl showed an increased odds ratio (OR) of 2.640 (P = 0.033). Additionally, HbA1c was associated with an increased risk of CKD in patients with HbA1c values ≥7%. Conclusions: The short-term glucose variability expressed by 2hPG-FPG is closely associated with decreased eGFR and an increased risk of CKD in patients with poor glycemic control (HbA1c≥7%). [ABSTRACT FROM AUTHOR]

Linkage maps enable the study of important biological questions. The construction of high-density linkage maps appears more feasible since the advent of next-generation sequencing (NGS), which eases SNP discovery and high-throughput genotyping of large population. However, the marker number explosion and genotyping errors from NGS data challenge the computational efficiency and linkage map quality of linkage study methods. Here we report the HighMap method for constructing high-density linkage maps from NGS data. HighMap employs an iterative ordering and error correction strategy based on a k-nearest neighbor algorithm and a Monte Carlo multipoint maximum likelihood algorithm. Simulation study shows HighMap can create a linkage map with three times as many markers as ordering-only methods while offering more accurate marker orders and stable genetic distances. Using HighMap, we constructed a common carp linkage map with 10,004 markers. The singleton rate was less than one-ninth of that generated by JoinMap4.1. Its total map distance was 5,908 cM, consistent with reports on low-density maps. HighMap is an efficient method for constructing high-density, high-quality linkage maps from high-throughput population NGS data. It will facilitate genome assembling, comparative genomic analysis, and QTL studies. HighMap is available at http://highmap.biomarker.com.cn/. [ABSTRACT FROM AUTHOR]

The lysin LysGH15, which is derived from the staphylococcal phage GH15, demonstrates a wide lytic spectrum and strong lytic activity against methicillin-resistant Staphylococcus aureus (MRSA). Here, we find that the lytic activity of the full-length LysGH15 and its CHAP domain is dependent on calcium ions. To elucidate the molecular mechanism, the structures of three individual domains of LysGH15 were determined. Unexpectedly, the crystal structure of the LysGH15 CHAP domain reveals an “EF-hand-like” calcium-binding site near the Cys-His-Glu-Asn quartet active site groove. To date, the calcium-binding site in the LysGH15 CHAP domain is unique among homologous proteins, and it represents the first reported calcium-binding site in the CHAP family. More importantly, the calcium ion plays an important role as a switch that modulates the CHAP domain between the active and inactive states. Structure-guided mutagenesis of the amidase-2 domain reveals that both the zinc ion and E282 are required in catalysis and enable us to propose a catalytic mechanism. Nuclear magnetic resonance (NMR) spectroscopy and titration-guided mutagenesis identify residues (e.g., N404, Y406, G407, and T408) in the SH3b domain that are involved in the interactions with the substrate. To the best of our knowledge, our results constitute the first structural information on the biochemical features of a staphylococcal phage lysin and represent a pivotal step forward in understanding this type of lysin. [ABSTRACT FROM AUTHOR]

Objective: Chronic low-grade inflammation has long been recognized as the central link between obesity and type 2 diabetes (T2D). The novel subset of T helper (Th) cells, Th22, plays an emerging role in chronic inflammation. We investigated the potential association between Th22 and the pathogenesis of obesity and T2D. Methods: Ninety T2D inpatients (T2D group), 30 healthy participants with BMI ranged from 19 to 23.9 kg/m2 (CTL group) and 30 metabolically healthy obese controls with BMI ≥ 30 kg/m2 (MHO group) were employed in our study. Peripheral frequencies of Th22 and Th1 and Th17 cells were determined by flow cytometry based on their specific cytokine patterns. Cytokine levels in fresh plasma were quantified by ELISA. Results: Compared to that in CTL group (1.18±0.06%, n = 28), peripheral frequency of Th22 cells was significantly increased in MHO group (1.88±0.10%, n = 30) and in T2D group (2.247±0.10%, n = 89). There was a consistent notable increase in plasma interleukin (IL)-22 of T2D patients [47.56 (30.55–76.89) pg/mL] as compared with that of MHO group [36.65 (29.52–55.70) pg/ml; *P<0.0001] and CTLs [36.33 (31.93–40.62) pg/mL; *P<0.0001]. Furthermore, other than Th1/Th17, previously frequently described participants in obesity and T2D, there was a strong correlation between Th22 frequency and the homeostasis model of assessment for insulin resistance index (r = 0.6771, *P<0.0001) and HOMA for β-cell function (r = −0.7264, *P<0.0001). Conclusions: There were increased Th22 frequencies and IL-22 levels in obesity and T2D. Elevated Th22 and IL-22 also aided in the differentiation of MHO from T2D patients. The notable correlation implied that Th22 might play a more determinant role in both insulin resistance and β-cell impairment. [ABSTRACT FROM AUTHOR]

Background: The radiation-induced energy metabolism dysfunction related to injury and radiation doses is largely elusive. The purpose of this study is to investigate the early response of energy metabolism in small intestinal tissue and its correlation with pathologic lesion after total body X-ray irradiation (TBI) in Tibet minipigs. Methods and Results: 30 Tibet minipigs were assigned into 6 groups including 5 experimental groups and one control group with 6 animals each group. The minipigs in these experimental groups were subjected to a TBI of 2, 5, 8, 11, and 14 Gy, respectively. Small intestine tissues were collected at 24 h following X-ray exposure and analyzed by histology and high performance liquid chromatography (HPLC). DNA contents in this tissue were also examined. Irradiation causes pathologic lesions and mitochondrial abnormalities. The Deoxyribonucleic acid (DNA) content-corrected and uncorrected adenosine-triphosphate (ATP) and total adenine nucleotides (TAN) were significantly reduced in a dose-dependent manner by 2–8 Gy exposure, and no further reduction was observed over 8 Gy. Conclusion: TBI induced injury is highly dependent on the irradiation dosage in small intestine and inversely correlates with the energy metabolism, with its reduction potentially indicating the severity of injury. [ABSTRACT FROM AUTHOR]

Large-scale genotyping plays an important role in genetic association studies. It has provided new opportunities for gene discovery, especially when combined with high-throughput sequencing technologies. Here, we report an efficient solution for large-scale genotyping. We call it specific-locus amplified fragment sequencing (SLAF-seq). SLAF-seq technology has several distinguishing characteristics: i) deep sequencing to ensure genotyping accuracy; ii) reduced representation strategy to reduce sequencing costs; iii) pre-designed reduced representation scheme to optimize marker efficiency; and iv) double barcode system for large populations. In this study, we tested the efficiency of SLAF-seq on rice and soybean data. Both sets of results showed strong consistency between predicted and practical SLAFs and considerable genotyping accuracy. We also report the highest density genetic map yet created for any organism without a reference genome sequence, common carp in this case, using SLAF-seq data. We detected 50,530 high-quality SLAFs with 13,291 SNPs genotyped in 211 individual carp. The genetic map contained 5,885 markers with 0.68 cM intervals on average. A comparative genomics study between common carp genetic map and zebrafish genome sequence map showed high-quality SLAF-seq genotyping results. SLAF-seq provides a high-resolution strategy for large-scale genotyping and can be generally applicable to various species and populations. [ABSTRACT FROM AUTHOR]

Inbred mini-pigs are ideal organ donors for future human xenotransplantations because of their clear genetic background, high homozygosity, and high inbreeding endurance. In this study, we chose fibroblast cells from a highly inbred pig line called Banna mini-pig inbred line (BMI) as donor nuclei for nuclear transfer, combining with transcription activator-like effector nucleases (TALENs) and successfully generated α-1,3-galactosyltransferase (GGTA1) gene biallelic knockout (KO) pigs. To validate the efficiency of TALEN vectors, in vitro-transcribed TALEN mRNAs were microinjected into one-cell stage parthenogenetically activated porcine embryos. The efficiency of indel mutations at the GGTA1-targeting loci was as high as 73.1% (19/26) among the parthenogenetic blastocysts. TALENs were co-transfected into porcine fetal fibroblasts of BMI with a plasmid containing neomycin gene. The targeting efficiency reached 89.5% (187/209) among the survived cell clones after a 10 d selection. More remarkably 27.8% (58/209) of colonies were biallelic KO. Five fibroblast cell lines with biallelic KO were chosen as nuclear donors for somatic cell nuclear transfer (SCNT). Three miniature piglets with biallelic mutations of the GGTA1 gene were achieved. Gal epitopes on the surface of cells from all the three biallelic KO piglets were completely absent. The fibroblasts from the GGTA1 null piglets were more resistant to lysis by pooled complement-preserved normal human serum than those from wild-type pigs. These results indicate that a combination of TALENs technology with SCNT can generate biallelic KO pigs directly with high efficiency. The GGTA1 null piglets with inbred features created in this study can provide a new organ source for xenotransplantation research. [ABSTRACT FROM AUTHOR]

In recent times, improvements in smart mobile devices have led to new functionalities related to their embedded positioning abilities. Many related applications that use positioning data have been introduced and are widely being used. However, the positioning data acquired by such devices are prone to erroneous values caused by environmental factors. In this research, a detection algorithm is implemented to detect erroneous data over a continuous positioning data set with several options. Our algorithm is based on a moving window for speed values derived by consecutive positioning data. Both the moving average of the speed and standard deviation in a moving window compose a moving significant interval at a given time, which is utilized to detect erroneous positioning data along with other parameters by checking the newly obtained speed value. In order to fulfill the designated operation, we need to examine the physical parameters and also determine the parameters for the moving windows. Along with the detection of erroneous speed data, estimations of correct positioning are presented. The proposed algorithm first estimates the speed, and then the correct positions. In addition, it removes the effect of errors on the moving window statistics in order to maintain accuracy. Experimental verifications based on our algorithm are presented in various ways. We hope that our approach can help other researchers with regard to positioning applications and human mobility research. [ABSTRACT FROM AUTHOR]

Background: Many reports have shown inconsistent results on the relationship between single nucleotide polymorphisms (SNPs) of X-ray repair cross complementing protein (XRCC1) gene and platinum-based chemotherapeutic efficacy. This meta-analysis aimed to summarize published data about the association between two SNPs of XRCC1 (Arg194Trp and Arg399Gln) and treatment outcomes of patients with advanced gastric cancer. Methodology/Principal Findings: We retrieved the relevant articles from MEDLINE, Web of Knowledge, and the China National Knowledge Infrastructure (CNKI) databases. Studies were selected according to specific inclusion and exclusion criteria. Study quality was assessed according to the guidelines outlined by Hayden, et al. and PRISMA guidelines. We estimated the odds ratio (OR) for response rate versus no response after platinum-based chemotherapy. Progression-free survival (PFS) and overall survival (OS) were evaluated by pooled Cox proportional hazard ratios (HRs) and 95% confidence intervals (CIs). We found that none of the XRCC1 Arg194Trp and Arg399Gln polymorphisms was significantly associated with tumor response. Stratified analysis by ethnicity or sensitivity analysis also showed that XRCC1 SNPs were not related with chemotherapy response. Patients with minor variant A allele were likely to have poorer 2-year survival rate than those with G/G genotype. However, in the group of 5-year follow up, there was no significant association between the A allele and OS yet. Conclusions/Significance: There is no evidence to support the use of XRCC1 Arg194Trp and Arg399Gln polymorphisms as prognostic predictors of TR and PFS in gastric patients treated with platinum-based chemotherapy. The relationship between minor variant A allele and OS requires further verification. [ABSTRACT FROM AUTHOR]