The genome of the Paleogene relic tree Bretschneidera sinensis: insights into trade-offs in gene family evolution, demographic history, and adaptive SNPs.

Among relic species, genomic information may provide the key to inferring their long-term survival. Therefore, in this study, we investigated the genome of the Paleogene relic tree species, Bretschneidera sinensis, which is a rare endemic species within southeastern Asia. Specifically, we assembled a high-quality genome for B. sinensis using PacBio high-fidelity and high-throughput chromosome conformation capture reads and annotated it with long and short RNA sequencing reads. Using the genome, we then detected a trade-off between active and passive disease defences among the gene families. Gene families involved in salicylic acid and MAPK signalling pathways expanded as active defence mechanisms against disease, but families involved in terpene synthase activity as passive defences contracted. When inferring the long evolutionary history of B. sinensis, we detected population declines corresponding to historical climate change around the Eocene-Oligocene transition and to climatic fluctuations in the Quaternary. Additionally, based on this genome, we identified 388 single nucleotide polymorphisms (SNPs) that were likely under selection, and showed diverse functions in growth and stress responses. Among them, we further found 41 climate-associated SNPs. The genome of B. sinensis and the SNP dataset will be important resources for understanding extinction/diversification processes using comparative genomics in different lineages.

The complete chloroplast genome of Ormosia purpureiflora (Fabaceae).

Ormosia purpureiflora is endemic to China. It is named after its purple flowers. It is a small tree only up to 3 m. It has leathery leaves, racemose inflorescences. The seeds are elliptic and red in coat. It is only confined to Luofushan Provincial Nature Reserve in Huizhou of Guangdong Province. Herein, we first reported on its complete chloroplast genome sequence as genomic resource for conservation purposes. The chloroplast genome of O. purpureiflora was 173,364 bp in length, with a large single-copy region of 73,465 bp, a small single-copy region of 18,751 bp, and a pair of inverted repeat regions that were 40,574 bp each. A total of 90 protein-coding genes, 38 transfer RNA genes, and eight ribosomal RNA genes were predicted, while 106 simple sequence repeats were recorded throughout the genome. Phylogenetic analysis revealed that O. purpureiflora was sister to O. emarginata.

Global blue carbon accumulation in tidal wetlands increases with climate change.

Coastal tidal wetlands produce and accumulate significant amounts of organic carbon (C) that help to mitigate climate change. However, previous data limitations have prevented a robust evaluation of the global rates and mechanisms driving C accumulation. Here, we go beyond recent soil C stock estimates to reveal global tidal wetland C accumulation and predict changes under relative sea level rise, temperature and precipitation. We use data from literature study sites and our new observations spanning wide latitudinal gradients and 20 countries. Globally, tidal wetlands accumulate 53.65 (95%CI: 48.52-59.01) Tg C yr-1, which is ∼30% of the organic C buried on the ocean floor. Modeling based on current climatic drivers and under projected emissions scenarios revealed a net increase in the global C accumulation by 2100. This rapid increase is driven by sea level rise in tidal marshes, and higher temperature and precipitation in mangroves. Countries with large areas of coastal wetlands, like Indonesia and Mexico, are more susceptible to tidal wetland C losses under climate change, while regions such as Australia, Brazil, the USA and China will experience a significant C accumulation increase under all projected scenarios.

Faster recovery of soil biodiversity in native species mixture than in Eucalyptus monoculture after 60 years afforestation in tropical degraded coastal terraces.

Afforestation is an effective method to restore degraded land. Afforestation methods vary in their effects on ecosystem multifunctionality, but their effects on soil biodiversity have been largely overlooked. Here, we mapped the biodiversity and functioning of multiple soil organism groups resulting from diverse afforestation methods in tropical coastal terraces. Sixty years after afforestation from bare land (BL), plant species richness and the abundance of plant litter (398 ± 85 g m-2 ) and plant biomass (179 ± 3.7 t ha-1 ) in native tree species mixtures (MF) were restored to the level of native forests (NF; 287 ± 21 g m-2 and 243.0 ± 33 t ha-1 , respectively), while Eucalyptus monoculture (EP) only successfully restored the litter mass (388 ± 43 g m-2 ) to the level of NF. Soil fertility in EP and MF was increased but remained lower than in NF. For example, soil nitrogen and phosphorus concentrations in MF (1.2 ± 0.2 g kg-1 and 408 ± 49 mg kg-1 , respectively; p < 0.05) were lower than in NF (1.8 ± 0.2 g kg-1 and 523 ± 24 mg kg-1 , respectively; p < 0.05). Soil biodiversity, abundance (except for nematodes), and community composition in MF were similar or greater than those in NF. In contrast, restoration with EP only enhanced the diversity of microbes and mites to the level of NF, but not for other soil biota. Together, afforestation with native species mixtures can end up restoring vegetation and most aspects of the taxonomic and functional biodiversity in soil whereas monoculture using fast-growing non-native species cannot. Native species mixtures show a greater potential to reach completely similar levels of soil biodiversity in local natural forests if they are received some more decades of afforestation. Multifunctionality of soil biotic community should be considered to accelerate such processes in future restoration practices.

Phosphorus addition decreases microbial residual contribution to soil organic carbon pool in a tropical coastal forest.

The soil nitrogen (N) and phosphorus (P) availability often constrains soil carbon (C) pool, and elevated N deposition could further intensify soil P limitation, which may affect soil C cycling in these N-rich and P-poor ecosystems. Soil microbial residues may not only affect soil organic carbon (SOC) pool but also impact SOC stability through soil aggregation. However, how soil nutrient availability and aggregate fractions affect microbial residues and the microbial residue contribution to SOC is still not well understood. We took advantage of a 10-year field fertilization experiment to investigate the effects of nutrient additions, soil aggregate fractions, and their interactions on the concentrations of soil microbial residues and their contribution to SOC accumulation in a tropical coastal forest. We found that continuous P addition greatly decreased the concentrations of microbial residues and their contribution to SOC, whereas N addition had no significant effect. The P-stimulated decreases in microbial residues and their contribution to SOC were presumably due to enhanced recycling of microbial residues via increased activity of residue-decomposing enzymes. The interactive effects between soil aggregate fraction and nutrient addition were not significant, suggesting a weak role of physical protection by soil aggregates in mediating microbial responses to altered soil nutrient availability. Our data suggest that the mechanisms driving microbial residue responses to increased N and P availability might be different, and the P-induced decrease in the contribution of microbial residues might be unfavorable for the stability of SOC in N-rich and P-poor tropical forests. Such information is critical for understanding the role of tropical forests in the global carbon cycle.

Leaf nonstructural carbohydrate concentrations of understory woody species regulated by soil phosphorus availability in a tropical forest.

Leaf soluble sugars and starch are important components of nonstructural carbohydrates (NSCs), which are crucial for plant growth, development, and reproduction. Although there is a large body of research focusing on the regulation of plant NSC (soluble sugars and starch) concentrations, the response of foliar NSC concentrations to continuous nitrogen (N) and phosphorus (P) addition is still unclear, especially in tropical forests. Here, we used a long-term manipulative field experiment to investigate the response of leaf NSC concentrations to continuous N and P addition (3-, 5-, and 8-year fertilization) in a tropical forest in southern China. We found significant species-specific variation in leaf NSC concentrations in this tropical forest. Phosphorus addition dramatically decreased both leaf soluble sugar and starch concentrations, while N addition had no significant effects on leaf soluble sugar and starch concentrations. These results suggest that, in plants growing in P-limiting tropical soil, leaf NSC concentrations are regulated by soil P availability rather than N availability. Moreover, the negative relationships between NSC concentrations and leaf mass per area (LMA) revealed that NSCs could supply excess carbon (C) for leaf expansion under P addition. This was further supported by the increased structural P fraction after P fertilization in our previous study at the same site. We conclude that soil P availability strongly regulates leaf starch and soluble sugar concentrations in the tropical tree species included in this study. The response of leaf NSC concentrations to long-term N and P addition can reflect the close relationships between plant C dynamics and soil nutrient availability in tropical forests. Maintaining relatively higher leaf NSC concentrations in tropical plants can be a potential mechanism for adapting to P-deficient conditions.

Changes in seasonal precipitation distribution but not annual amount affect litter decomposition in a secondary tropical forest.

In the tropics of South China, climate change induced more rainfall events in the wet season in the last decades. Moreover, there will be more frequently spring drought in the future. However, knowledge on how litter decomposition rate would respond to these seasonal precipitation changes is still limited. In the present study, we conducted a precipitation manipulation experiment in a tropical forest. First, we applied a 60% rainfall exclusion in April and May to defer the onset of wet season and added the same amount of water in October and November to mimic a deferred wet season (DW); second, we increased as much as 25% mean annual precipitation into plots in July and August to simulate a wetter wet season (WW). Five single-species litters, with their carbon to nitrogen ratio ranged from 27 to 49, and a mixed litter were used to explore how the precipitation change treatments would affect litter decomposition rate. The interaction between precipitation changes and litter species was not significant. The DW treatment marginally accelerated litter decomposition across six litter types. Detailed analysis showed that DW increased litter decomposition rate in the periods of January to March and October to December, when soil moisture was increased by the water addition in the dry season. In contrast, WW did not significantly affect litter decomposition rate, which was consistent with the unchanged soil moisture pattern. In conclusion, the study indicated that regardless of litter types or litter quality, the projected deferred wet season would increase litter decomposition rate, whereas the wetter wet season would not affect litter decomposition rate in the tropical forests. This study improves our knowledge of how tropical forest carbon cycling in response to precipitation change.

Tumor-infiltrating FoxP3+ Tregs predict favorable outcome in colorectal cancer patients: A meta-analysis.

FoxP3+ regulatory T cells (FoxP3+ Tregs) are considered to be a key mediator in immune escape and tumor progression. However, the role of FoxP3+ Tregs in human colorectal cancer (CRC) remains controversial. Herein, we conducted a meta-analysis including 17 published studies with 3811 patients identified from PubMed and EBSCO to assess the prognostic impact of tumor-infiltrating FoxP3+ Tregs in human CRC. We found FoxP3+ Tregs infiltrating into both intraepithelium and stroma within tumor were significantly positively correlated with 1, 3, 5 and 10-year overall survival (OS), but not with 1, 3, 5-year disease-free survival (DFS) of patients. Interestingly, in stratified analyses by compartments within tumor FoxP3+ Tregs infiltrating into, FoxP3+ Tregs invading stromal compartment significantly improved 3 and 5-year OS, yet OS wasn't improved when FoxP3+ Tregs infiltrated into intraepithelium only. Furthermore, FoxP3+ Tregs invading both intraepithelium and stroma significantly inversely correlated with TNM stage of CRC. In conclusion, High density of FoxP3+ Tregs within tumor especially at stromal compartment leads to a favorable outcome in CRC, implicating FoxP3+ Tregs are one of valuable indexes for prognostic prediction in human CRC.

Prognostic role of intratumoral IL-17A expression by immunohistochemistry in solid tumors: a meta-analysis.

IL-17A is an important proinflammatory cytokine which is frequently elevated in tumor microenvironment. However, the role of intratumoral IL-17A in solid tumors remains controversial. Herein, we conducted a meta-analysis to assess the prognostic impact of intratumoral IL-17A in patients with solid tumor. PubMed and EBSCO were searched to identify the studies evaluating the associations between intratumoral IL-17A measured by immunohistochemistry (IHC) and overall survival (OS) and disease-free survival (DFS) in solid tumors. A total of 2972 patients with solid tumor from 21 published studies were incorporated into this meta-analysis. We found that high level of intratumoral IL-17A was significantly associated with worse 3-year, 5-year OS and 1-year, 3-year DFS, but not with 1-year OS or 5-year DFS in solid tumors. In addition, in stratified analyses by cancer types, IL-17A overexpression was significantly associated with worse OS in hepatic carcinoma, but with improved OS in esophageal squamous cell carcinoma (ESCC). Furthermore, high IL-17A expression positively correlated with advanced TNM stage. In conclusion, High expression of intratumoral IL-17A leads to an unfavorable clinical outcome in majority of solid tumors, implicating IL-17A is a valuable biomarker for prognostic prediction of human solid malignances and targeting it may have a potential for effective treatment.

Reforestation in southern China: revisiting soil N mineralization and nitrification after 8 years restoration.

Nitrogen availability and tree species selection play important roles in reforestation. However, long-term field studies on the effects and mechanisms of tree species composition on N transformation are very limited. Eight years after tree seedlings were planted in a field experiment, we revisited the site and tested how tree species composition affects the dynamics of N mineralization and nitrification. Both tree species composition and season significantly influenced the soil dissolved organic carbon (DOC) and nitrogen (DON). N-fixing Acacia crassicarpa monoculture had the highest DON, and 10-mixed species plantation had the highest DOC. The lowest DOC and DON concentrations were both observed in Eucalyptus urophylla monoculture. The tree species composition also significantly affected net N mineralization rates. The highest rate of net N mineralization was found in A. crassicarpa monoculture, which was over twice than that in Castanopsis hystrix monoculture. The annual net N mineralization rates of 10-mixed and 30-mixed plantations were similar as that of N-fixing monoculture. Since mixed plantations have good performance in increasing soil DOC, DON, N mineralization and plant biodiversity, we recommend that mixed species plantations should be used as a sustainable approach for the restoration of degraded land in southern China.

Assessment of Retrograde Coronary Venous Infusion of Mesenchymal Stem Cells Combined with Basic Fibroblast Growth Factor in Canine Myocardial Infarction Using Strain Values Derived from Speckle-Tracking Echocardiography.

Speckle-tracking echocardiography was used to assess retrograde coronary venous infusion of mesenchymal stem cells (MSCs) combined with basic fibroblast growth factor (bFGF) in a canine model of acute myocardial infarction (AMI). AMI was induced by ligation of the left anterior descending coronary artery. Coronary venous retroperfusion was performed at 1 wk after AMI. Twenty-eight animals were randomized into four groups: saline, bFGF+saline, saline+MSCs and bFGF+MSCs. Echocardiography was performed before AMI, at 7 d post-AMI and 40 d after retroperfusion. Apoptotic cardiomyocytes in the border zone of the ischemic region were evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling. Vascular endothelial growth factor and factor VIII concentrations were measured by western blotting. The left ventricular end-systolic volume increased significantly, whereas the left ventricular ejection fraction and global and segmental strain values decreased significantly after AMI. After retroperfusion, the strain values of the infarct zone, but not conventional echocardiographic parameters, were significantly different between control and bFGF+MSC groups. Cardiomyocyte apoptosis decreased, whereas vascular endothelial growth factor and factor VIII concentrations were higher in the bFGF+MSC, bFGF and MSC groups. Cardiomyocyte apoptosis was well correlated with the strain values. Although retrograde coronary venous infusion of bFGF and MSCs promoted neo-vascularization of the infarcted myocardium and inhibited apoptosis, there was only a slight strain improvement without a substantial increase in global cardiac functions.

Analysis of etiology, chromosome and prognosis for small left heart system development in 69 fetuses.

OBJECTIVE: To provide a basis for evaluating the prognosis of small left heart system development in fetuses, we analyzed its related factors. METHODS: The fetal echocardiogram was performed in 3859 pregnant women, and then small left heart system development was identified in 69 fetuses. The data of prenatal and postnatal echocardiograms, postnatal cardiac surgical treatment, chromosome and autopsy after induced labor were analyzed in the 69 fetuses. RESULTS: Except 1320 cases losing follow-up, 2539 cases had complete data. Among the 2539 cases, small left heart system development was identified in 69 fetuses. Of the 69 fetuses, 12 had hypoplastic left heart syndrome, 20 premature closure of foramen ovale, 13 total anomalous pulmonary venous drainage, 2 common pulmonary vein lumen atresia, 21 aortic coarctation or interruption and 1 right pulmonary hypoplasia. Among the 69 fetuses, chromosome abnormality was found in 7. CONCLUSION: There are many etiological factors causing small left heart system development. The prognosis is poor in the fetuses with hypoplastic left heart syndrome, common pulmonary vein lumen atresia, pulmonary hypoplasia, other malformations or/and chromosome abnormality. Fetal echocardiography combined with chromosome examination can provide important bases for making diagnosis and evaluating the prognosis regarding small left heart system development.

Doppler Echocardiographic Measurements in Normal Chinese Adults (EMINCA): a prospective, nationwide, and multicentre study.

AIMS: Currently, available Doppler echocardiographic reference values are derived mainly from North American and European population studies, which may not applicable to the Chinese population. We aimed to establish normal reference values of Doppler echocardiographic parameters in a nationwide, population-based cohort of healthy Han Chinese adults. METHODS AND RESULTS: A total of 1394 qualified healthy subjects (mean age 47.3 ± 16.0 years, 678 men) were enrolled at 43 collaborating laboratories, 37 transvalvular flow and tissue Doppler parameters were obtained, and the impacts of gender and age on each parameter were analysed. Significant differences were found between men and women in 48.6% (18/37) of the parameters analysed, and among different age groups in 83.8% (31/37) of the parameters in men and in 86.5% (32/37) of the parameters in women. CONCLUSIONS: Normal reference values of Doppler echocardiographic parameters were established for the first time in a nationwide, population-based cohort of healthy Han Chinese adults. Since most of these parameters differed by gender and/or age, reference values specified for gender and age should be recommended in clinical practice.

Echocardiographic measurements in normal chinese adults focusing on cardiac chambers and great arteries: a prospective, nationwide, and multicenter study.

BACKGROUND: Currently available echocardiographic reference values are derived mainly from North American and European population studies, and no echocardiographic reference values are available for the Chinese population. The aim of this study was to establish normal values of echocardiographic measurements of the cardiac chambers and great arteries in a nationwide, population-based cohort of healthy Han Chinese adults. METHODS: A total of 1,586 healthy Han Chinese volunteers aged 18 to 79 years were screened at 43 collaborating laboratories throughout China. Standard M-mode and two-dimensional echocardiography was performed to obtain measurements of the cardiac chambers and great arteries. The impacts of gender and age on all echocardiographic measurements were analyzed. RESULTS: A total of 1,394 qualified healthy subjects (mean age, 47.3 ± 16.0 years; 678 men) were ultimately enrolled. Except for left ventricular ejection fraction, values of cardiac chamber and great arterial dimensions were significantly higher in men than in women. Most measurements of the atrial and great arterial dimensions, left ventricular wall thickness, and left ventricular mass increased with age in both men and women. CONCLUSIONS: Normal reference values of cardiac dimensional parameters were established for the first time in a nationwide, population-based cohort of healthy Han Chinese adults. Because most of these parameters were found to vary with gender and age, reference values stratified for gender and age should be used in clinical practice.

Early detection of regional and global left ventricular myocardial function using strain and strain-rate imaging in patients with metabolic syndrome.

BACKGROUND: Strain and strain-rate imaging (SRI) have been found clinically useful in the assessment of cardiac systolic and diastolic function as well as providing new insights in deciphering cardiac physiology and mechanics in cardiomyopathies, and identifying early subclinical changes in various pathologies. The aim of this study was to evaluate the regional and global left ventricular (LV) myocardial function in metabolic syndrome (MS) with SRI so that we can provide more myocardial small lesions in patients with MS, which is robust and reliable basis for early detection of LV function. METHODS: Thirty-nine adults with MS were enrolled in the study. There was a control group of 39 healthy adults. In addition to classic echocardiographic assessment of LV global functional changes, SRI was used to evaluate regional and global LV function. Including: Peak systolic strain (S), peak systolic strain-rate (SR-s), peak diastolic strain-rate (SR-e). RESULTS: There were no statistically significant differences between MS and controls in all traditional parameters of LV systolic function. On the other hand, significant differences were observed between MS and the control group in most of the parameters of S, SR-s, SR-e in regional LV function. Multiple stepwise regression analyses revealed that S and SR significantly were negatively correlated with blood pressure, waist circumference, fasting plasma glucose, uric acid, suggesting that risk factories were relevant to regional systolic dysfunction. CONCLUSION: In MS with normal LV ejection fraction, there was regional myocardial dysfunction, risk factors contributed to the impairment of systolic and diastolic function of the regional myocardium. Assessment of myocardial function using SRI could be more accurate in MS patient evaluation than conventional echocardiography alone.

Right atrial cardiac rhabdomyoma with premature foramen ovale restriction: A case report.

Fetal cardiac rhabdomyoma is the most common cardiac tumor in fetuses. However, this benign tumor can cause hemodynamic repercussions and intrauterine fetal mortality. The present study reports a case of rare fetal cardiac rhabdomyoma located in the right atrium, accompanied by premature restriction of the foramen ovale and moderate pericardial effusion, as determined by tomographic ultrasound imaging (TUI). Fetal mortality subsequently occurred late in the second trimester of pregnancy and the diagnosis was confirmed by pathology. The present study discusses the occurrence and diagnosis of this rare abnormality. TUI mode with spatio-temporal image correlation offline imaging provides the physician with clear views of abnormal intracardiac structures in the beating heart. With improvements in sonographic technology, the diagnosis of fetal cardiac rhabdomyoma may be easier and more accurate in the clinical arena.

Left anterior descending coronary artery flow impaired by right ventricular apical pacing: the role of systolic dyssynchrony.

INTRODUCTION: Right ventricular (RV) pacing may affect myocardial perfusion and coronary blood flow; however, it remains unknown whether this is related to systolic dyssynchrony induced by RV pacing. This prospective study was aimed to assess the relationship between dyssynchrony and the changes of coronary blood flow. METHODS: Seventy patients with sinus node dysfunction were prospectively enrolled. Coronary flow was evaluated by measuring diastolic velocity time integral (VTI) and duration at the distal-portion of left anterior descending coronary artery (LAD) with transthoracic echocardiography at baseline and follow-up. Systolic dyssynchrony was assessed with tissue Doppler imaging by time standard deviation to peak systolic velocity of 12 left ventricular segments (Ts-SD, cutoff value ≥ 33 ms). RESULTS: Adequate data for analysis was available from 65 patients. At follow-up (mean follow up time: 127 ± 45 days), LAD velocity-time integral (LAD-VTI: 12.1 ± 4.2 vs. 10.7 ± 4.6 cm, p<0.001) was decreased and there was deterioration of left ventricular systolic function (left ventricular ejection fraction: 65 ± 7% vs. 62 ± 7%). However, these changes were only detected in those with RV pacing induced systolic dyssynchrony. Significant reduction of LAD-VTI (defined as ≥ 5%) occurred in 34 (52%) patients which was more prevalent in those with pacing-induced systolic dyssynchrony than those without (85.3% versus 16.1%, χ(2)=31.1, p<0.001). Though similar at baseline, LAD-VTI was significantly lower in the dyssynchrony group at follow up (p<0.001). Cox-regression analysis showed that pacing-inducing systolic dyssynchrony [hazard ratio (HR): 3.62, p=0.009] and higher accumulative pacing percentage (HR: 1.02, p=0.002) were independently associated with reduction of LAD-VTI. ROC curve demonstrated that accumulative pacing percentage ≥ 35% was 97% sensitive and 84% specific in revealing significant reduction (area under the curve: 0.961, p<0.001). CONCLUSIONS: RV pacing induced dyssynchrony is associated with reduced coronary flow and this may account for, in part, the deleterious effect of RV pacing on ventricular function over time.

Contrasting effects of silicates on cadmium uptake by three dicotyledonous crops grown in contaminated soil.

The effects of several silicates (talcum powder (TP), calcium silicate (CS), sodium silicate (SS), and potassium silicate (PS)), in comparison with other amendments (quicklime (QL) and potassium dihydrogen phosphate (PDP)) on cadmium (Cd) uptake by three dicotyledonous crops (Amaranthus hypochondriacus L. Cv. 'K112', Amaranthus tricolor L., and Brassica oleracea var. albiflora Kuntze) were investigated in Cd-contaminated soil. The effects of both application methods of amendments (singly and combined) and timing of application were also evaluated. Sodium silicate was the most effective in reducing crop Cd uptake and translocation, which was diminished by 51% in roots, 53% in stems, and 72% in leaves on average. Application of CS amendment showed greater efficiency than PDP amendment in decreasing Cd uptake by crops and resulted in increased biomass. Potassium silicate only slightly decreased shoot Cd concentration. Combination of PDP and SS was able to overcome the inhibitory effect of SS on crop yield while decreasing Cd concentrations in roots, stems and leaves of the tested crops by average rates of 52, 65, and 68% respectively. Applications of SS and PS significantly reduced the root-to-shoot Cd transfer factor. We found that Si accumulation in crops was not associated with lower Cd concentration, indicating that Si in crops may play a major role in alleviating metal stress rather than inhibiting crop Cd accumulation. We suggested that the inhibitive effect of silicates on crops Cd uptake was majorly attributed to the properties of the silicates, those were their specific effects on soil pH and cations, which increased Cd adsorption by soil and suppressed Cd uptake from soil solution by increasing the relative dissolved concentrations of competing cations.

Utility of echocardiographic tissue synchronization imaging to redirect left ventricular epicardial lead placement for cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) with biventricular pacing has demonstrated cardiac function improvement for treating congestive heart failure (HF). It has been documented that the placement of the left ventricular lead at the longest contraction delay segment has the optimal CRT benefit. This study described follow-up to surgical techniques for CRT as a viable alternative for patients with heart failure. METHODS: Between April 2007 and June 2012, a total of 14 consecutive heart failure patients with New York Heart Association (NYHA) Class III-IV underwent left ventricular epicardial lead placements via surgical approach. There were eight males and six females, aged 36 to 79 years ((59.6 ± 9.2) years). The mean left ventricular ejection fraction (LVEF) was (33.6 ± 7.4)%. All patients were treated with left ventricular systolic dyssynchrony and underwent left ventricular epicardial lead placements via a surgical approach. Tissue Doppler imaging (TDI) and intraoperative transesophageal echocardiography were used to assess changes in left heart function and dyssynchronic parameters. Also, echo was used to select the best site for left ventricular epicardial lead placement. RESULTS: Left ventricular epicardial leads were successfully implanted in the posterior or lateral epicardial wall without serious complications in all patients. All patients had reduction in NYHA score from III-IV preoperatively to II-III postoperatively. The left ventricular end-diastolic diameter (LVEDD) decreased from (67.9 ± 12.7) mm to (61.2 ± 7.1) mm (P < 0.05), and LVEF increased from (33.6 ± 7.4)% to (42.2 ± 8.8)% (P < 0.05). Left ventricular intraventricular dyssynchrony index decreased from (148.4 ± 31.6) ms to (57.3 ± 23.8) ms (P < 0.05). CONCLUSIONS: Minimally invasive surgical placement of the left ventricular epicardial lead is feasible, safe, and efficient. TDI can guide the epicardial lead placement to the ideal target location.

Ultrasound bio-microscopy for measurement of coronary artery flow and estimation of infarct size in a mouse model of acute myocardial infarction.

Ultrasound bio-microscopy was used to measure hemodynamic changes in the left main coronary artery after myocardial infarction (MI), and its usefulness in estimating infarct size was evaluated. MI was induced by left anterior descending artery ligation. Diastolic peak velocity (Vd), mean flow velocity (Vmean) and the velocity-time integral (VTI) were measured 2 and 6 h after MI. Serum troponin I levels were assayed 2, 6 and 12 h after MI. At 2 h, Vmean and VTI significantly differed between mice that underwent low and high left anterior descending artery ligation; Vd, Vmean and VTI were correlated with infarct size (r = -0.557, -0.693 and -0.672, respectively; all p < 0.01). Infarct size was more strongly correlated with 2-h ultrasound bio-microscopy measurements than with 2-h serum troponin I level. Measurement of coronary artery blood flow by ultrasound bio-microscopy may be useful for early estimation of infarct size in mice.