Accumulation of typical persistent organic pollutants and heavy metals in bioretention facilities: Distribution, risk assessment, and microbial community impact.

Bioretention facilities have proven highly effective in removing pollutants from runoff. However, there is a concerning paucity of research on the contamination characteristics and associated risks posed by refractory pollutants in these facilities following long-term operation. This research focuses on the distribution, sources, microbial community impact, and human health risks of pollutants in eight bioretention facilities that have been operational for 5-11 years. The results showed that the distribution of Cu, Zn, and Cd was closely related to anti-seepage measures. PAHs, PCBs, and OCPs primarily accumulated in the surface, with concentrations ranging from 7.42 to 20.34 mg/kg, 31.8-77.3 µg/kg, and 60.5-163.6 µg/kg, respectively. Their concentrations inversely correlate with the depth of the media. Although the majority of contaminants remained below their respective risk thresholds, their concentrations typically exceeded those of background soil values, indicating an enrichment phenomenon. Source analysis revealed that PAHs primarily originate from oil combustion, PCBs were linked to their related industrial products, DDTs had their main sources in technical DDx and residues from the use of dicofol, while HCHs were traced back to historical residues from agricultural activities. Microbial α-diversity (Chao 1 and Shannon) decreased by 8.3-23.4% and 0.8-4.4%, respectively, in different facilities after long-term operation. The most dominant microbial phylum in the facilities was Proteobacteria (all relative abundances >48%). The total relative abundance of dominant genera was 6.7-34.3% higher than the control site, and Pseudomonas, a typical POPs-heavy metal degrading bacterium, had the highest relative abundance (>1.2%). Cu, Zn, and Cd present no non-carcinogenic risks and have low potential ecological risks. However, the lifetime cancer risk for PAHs is 10-6 ∼10-4 in most facilities and is of concern. The cancer risk for PCBs is acceptable, while OCPs pose a low cancer risk only for children.

[Cluster Analysis and Ablation Success Rate in Atrial Fibrillation Patients Undergoing Catheter Ablation]. / æˆ¿é¢¤å°„é¢‘æ¶ˆèžæ‚£è€ çš„èšç±»åˆ†æžåŠæ¶ˆèžæˆåŠŸçŽ‡è¯„ä»·.

Objective: Atrial fibrillation (AF) is a disease of high heterogeneity, and the association between AF phenotypes and the outcome of different catheter ablation strategies remains unclear. Conventional classification of AF (e.g. according to duration, atrial size, and thromboembolism risk) fails to provide reference for the optimal stratification of the prognostic risks or to guide individualized treatment plan. In recent years, research on machine learning has found that cluster analysis, an unsupervised data-driven approach, can uncover the intrinsic structure of data and identify clusters of patients with pathophysiological similarity. It has been demonstrated that cluster analysis helps improve the characterization of AF phenotypes and provide valuable prognostic information. In our cohort of AF inpatients undergoing radiofrequency catheter ablation, we used unsupervised cluster analysis to identify patient subgroups, to compare them with previous studies, and to evaluate their association with different suitable ablation patterns and outcomes. Methods: The participants were AF patients undergoing radiofrequency catheter ablation at West China Hospital between October 2015 and December 2017. All participants were aged 18 years or older. They underwent radiofrequency catheter ablation during their hospitalization. They completed the follow-up process under explicit informed consent. Patients with AF of a reversible cause, severe mitral stenosis or prosthetic heart valve, congenital heart disease, new-onset acute coronary syndrome within three months prior to the surgery, or a life expectancy less than 12 months were excluded according to the exclusion criteria. The cohort consisted of 1102 participants with paroxysmal or persistent/long-standing persistent AF. Data on 59 variables representing demographics, AF type, comorbidities, therapeutic history, vital signs, electrocardiographic and echocardiographic findings, and laboratory findings were collected. Overall, data for the variables were rarely missing (<5%), and multiple imputation was used for correction of missing data. Follow-up surveys were conducted through outpatient clinic visits or by telephone. Patients were scheduled for follow-up with 12-lead resting electrocardiography and 24-hours Holter monitoring at 3 months and 6 months after the ablation procedure. Early ablation success was defined as the absence of documented AF, atrial flutter, or atrial tachycardia >30 seconds at 6-month follow-up. Hierarchical clustering was performed on the 59 baseline variables. All characteristic variables were standardized to have a mean of zero and a standard deviation of one. Initially, each patient was regarded as a separate cluster, and the distance between these clusters was calculated. Then, the Ward minimum variance method of clustering was used to merge the pair of clusters with the minimum total variance. This process continued until all patients formed one whole cluster. The "NbClust" package in R software, capable of calculating various statistical indices, including pseudo t2 index, cubic clustering criterion, silhouette index etc, was applied to determine the optimal number of clusters. The most frequently chosen number of clusters by these indices was selected. A heatmap was generated to illustrate the clinical features of clusters, while a tree diagram was used to depict the clustering process and the heterogeneity among clusters. Ablation strategies were compared within each cluster regarding ablation efficacy. Results: Five statistically driven clusters were identified: 1) the younger age cluster (n=404), characterized by the lowest prevalence of cardiovascular and cerebrovascular comorbidities but the highest prevalence of obstructive sleep apnea syndrome (14.4%); 2) a cluster of elderly adults with chronic diseases (n=438), the largest cluster, showing relatively higher rates of hypertension, diabetes, stroke, and chronic obstructive pulmonary disease; 3) a cluster with high prevalence of sinus node dysfunction (n=160), with patients showing the highest prevalence of sick sinus syndrome and pacemaker implantation; 4) the heart failure cluster (n=80), with the highest prevalence of heart failure (58.8%) and persistent/long-standing persistent AF (73.7%); 5) prior coronary artery revascularization cluster (n=20), with patients of the most advanced age (median: 69.0 years old) and predominantly male patients, all of whom had prior myocardial infarction and coronary artery revascularization. Patients in cluster 2 achieved higher early ablation success with pulmonary veins isolation alone compared to extensive ablation strategies (79.6% vs. 66.5%; odds ratio [OR]=1.97, 95% confidence interval [CI]: 1.28-3.03). Although extensive ablation strategies had a slightly higher success rate in the heart failure group, the difference was not statistically significant. Conclusions: This study provided a unique classification of AF patients undergoing catheter ablation by cluster analysis. Age, chronic disease, sinus node dysfunction, heart failure and history of coronary artery revascularization contributed to the formation of the five clinically relevant subtypes. These subtypes showed differences in ablation success rates, highlighting the potential of cluster analysis in guiding individualized risk stratification and treatment decisions for AF patients.

Creating and Stabilizing an Oxidized Pd Surface under Reductive Conditions for Photocatalytic Hydrogenation of Aromatic Carbonyls.

Photocatalysis provides an eco-friendly route for the hydrogenation of aromatic carbonyls to O-free aromatics, which is an important refining process in the chemical industry that is generally carried out under high pressure of hydrogen at elevated temperatures. However, aromatic carbonyls are often only partially hydrogenated to alcohols, which readily desorbs and are hardly further deoxygenated under ambient conditions. Here, we show that by constructing an oxide surface over the Pd cocatalyst supported on graphitic carbon nitride, an alternative hydrogenation path of aromatic carbonyls becomes available via a step-wise acetalization and hydrogenation, thus allowing efficient and selective production of O-free aromatics. The PdO surface allows for optimum adsorption of reactants and intermediates and rapid abstraction of hydrogen from the alcohol donor, favoring fast acetalization of the carbonyls and their consecutive hydrogenation to O-free hydrocarbons. The photocatalytic hydrogenation of benzaldehyde into toluene shows a high selectivity of >90% and a quantum efficiency of ∼10.2% under 410 nm irradiation. By adding trace amounts of HCl to the reaction solution, the PdO surface remains stable and active for long-term operation at high concentrations, offering perspective for practical applications.

Mitral Valve in Obstructive Hypertrophic Cardiomyopathy: Abnormalities, Management and Controversies.

Obstructive hypertrophic cardiomyopathy (obstructive HCM) is a hereditary disease characterized by septal hypertrophy and dynamic left ventricular outflow tract (LVOT) obstruction. Other than septal hypertrophy, mitral valve abnormalities are also quite common in patients with obstructive HCM, which may contribute to systolic anterior motion (SAM) of the mitral valve and LVOT obstruction. Surgical myectomy is the standard treatment to achieve anatomic correction of obstructive HCM, but controversies remain on whether and how the mitral valve procedures should be performed at the same time. In this review, we first described the mitral valve abnormalities in patients with obstructive HCM and their surgical corrections, we then explained the controversies based on current clinical studies, and we finally made a brief introduction on our surgical strategy and results.

Intracardiac thrombosis after congenital heart disease surgeries in neonates: a report of two cases.

BACKGROUND: Intracardiac thrombosis (ICT) is a rare complication after the cardiopulmonary surgery for interrupted aortic arch (IAA) or total anomalous pulmonary venous connection (TAPVC) without previous records. There are still no general guidelines regarding as the mechanism or management of postoperative ICT in neonates and younger infants. CASE PRESENTATION: We reported the conservative and surgical therapies in two neonates with intra-ventricular and intra-atrial thrombosis after the anatomical repair for IAA and TAPVC, respectively. There were no risk factors for ICT in both patients, except for the use of blood product and prothrombin complex concentrate. The surgery was indicated after TAPVC correction due to the worsening respiratory status and rapidly decreased mixed venous saturation. Anticoagulation combined with antiplatelet therapies was adopted in another patient. These two were both finally recovered, and three-month, six-month, and one-year follow-up echocardiography revealed no abnormality. CONCLUSIONS: ICT is uncommon in pediatric population after the surgery for congenital heart disease. Single ventricle palliation, heart transplantation, longer central line use, post-extracorporeal membrane oxygenation, and massive blood product use are major risk factors for postcardiotomy thrombosis. The causes of postoperative ICT are multifactorial, and the immaturity of thrombolytic and fibrinolytic system in neonates may serve as a prothrombotic factor. However, no consensus reached regarding as the therapies for postoperative ICT, and the large-scale prospective cohort study or randomized clinical trial is needed.

Widely targeted metabolomics analysis of different parts of kudzu.

Pueraria lobata is a traditional medicinal and edible plant. Its root is often used as a nutritional supplement, but its stems and leaves are often discarded. In this study, the types and contents of compounds in roots, stems and leaves of kudzu were studied by ultra-high-performance liquid chromatography electrospray ionization tandem mass spectrometry. A total of 446 metabolites were identified, which were mainly divided into eight categories; 40 unique compounds were detected in roots. Multivariate statistical analysis showed that there were significant differences in the contents of metabolites in the roots, stems and leaves of kudzu, and the most significant differences were found in the roots and stems. Most flavonoids and terpenoids accumulated in roots, while alkaloids, flavonoid glycosides, lignans and coumarins accumulated in stems and leaves. In addition, isoflavones accumulated least in stems and most in roots. These results improved our understanding of the accumulation of metabolites in kudzu and provided a reference for the full study of the medicinal value of different parts of kudzu.

Widely targeted metabolomics analysis reveals the differences in nonvolatile compounds of citronella before and after drying.

Citronella is used as a spice and a traditional herbal medicine. Dried citronella is easy to store and transport, and it is unclear whether dried citronella has more or fewer medicinal components compared to fresh citronella. In the present study, various metabolites in fresh and dry citronella were detected using a widely targeted metabolomics strategy. We identified 712 metabolites and classified them into 31 categories, and we identified 132 flavonoids. After citronella was dried, the quantities of most kinds of flavonoids increased, but the quantities of amino acids, organic acids, and vitamins decreased, and the quantity of quercetin increased significantly. Therefore, the medicinal value of dry citronella may have increased, and the nutritional value of amino acids and vitamins may have decreased. The results of this study can serve as a new theoretical reference to study citronella and promote its nutrition and medicinal chemical composition.

A Modular Tubular Flow System with Replaceable Photocatalyst Membranes for Scalable Coupling and Hydrogenation.

Heterogeneous photocatalysis is effective for the selective synthesis of value-added chemicals at lab-scale, yet falls short of requirements for mass production (low cost and user friendliness). Here we report the design and fabrication of a modular tubular flow system embedded with replaceable photocatalyst membranes for scalable photocatalytic C-C, C-N homocoupling and hydrogenation reactions, which can be operated in either circular and continuous flow mode with high performance. The photocatalyst membranes almost fully occupy the volume of the reactor, thus enabling optimal absorption of the incident light. Additionally, the porous structured photocatalyst membranes facilitate the mass transfer of the reactants to efficiently use the active sites, resulting in 0th -order reaction kinetics and a high space-time yield compared to the batch reaction system at practical application levels and prolonged reaction times.

Heterogeneous Photocatalytic Recycling of FeX2 /FeX3 for Efficient Halogenation of C-H Bonds Using NaX.

Environmental-friendly halogenation of C-H bonds using abundant, non-toxic halogen salts is in high demand in various chemical industries, yet the efficiency and selectivity of laboratory available protocols are far behind the conventional photolytic halogenation process which uses hazardous halogen sources. Here we report an FeX2 (X=Br, Cl) coupled semiconductor system for efficient, selective, and continuous photocatalytic halogenation using NaX as halogen source under mild conditions. Herein, FeX2 catalyzes the reduction of molecular oxygen and the consumption of generated oxygen radicals, thus boosting the generation of halogen radicals and elemental halogen for direct halogenation and indirect halogenation via the formation of FeX3 . Recycling of FeX2 and FeX3 during the photocatalytic process enables the halogenation of a wide range of hydrocarbons in a continuous flow, rendering it a promising method for applications.

Layer-specific strain echocardiography may reflect regional myocardial impairment in patients with hypertrophic cardiomyopathy.

Our study aimed to determine whether layer-specific strain (LSS) could reflect regional myocardial impairment in patients with hypertrophic cardiomyopathy (HCM). The study enrolled 50 patients with HCM and 30 age-matched healthy controls. Transmural gradient of longitudinal strain (TGLS), defined as the difference between the longitudinal strain of the endocardium and epicardium in a left ventricular segment, was used to reflect layer-specific myocardial impairment. Negative TGLS was consistently observed in healthy controls. The TGLS was relatively consistent within the basal, middle, and apical levels in healthy controls,but showed a significant gradient from the base towards the apex. In patients with HCM, the hypertrophic segments had significantly higher TGLS than the relatively normal segments or healthy controls at all 3 levels (0.14 % ± 3.48 % vs. -2.65 % ± 4.44 % vs. -2.17 % ± 1.66 % for basal, - 0.72 % ± 3.71 % vs. -4.02 % ± 4.00 % vs. -3.58 % ± 2.29 % for middle, and - 8.69 % ± 7.96 % vs. -11.44 % ± 6.65 % vs. -10.04 % ± 3.20 % for apex). Abnormal TGLS, defined as positive TGLS, in patients with HCM was associated with chest pain. In receiver operating characteristic curve analysis, a large area of abnormal TGLS (> 4 segments) had moderate accuracy for predicting chest pain (sensitivity, 73.3 %; specificity, 70.0 %). TGLS, a novel LSS derived parameter, may reflect regional myocardial impairment in patients with HCM.

Assessment on the cumulative effect of pollutants and the evolution of micro-ecosystems in bioretention systems with different media.

Bioretention system is one of the most used green stormwater infrastructures (GSI), and its media is a key factor in reducing runoff water volume and purifying water quality. Many studies have investigated media improvement to enhance the pollutant removal capacity. However, the long-term cumulative effect and microbial effect of pollutants in the modified-media bioretention system is less known. This study investigated the cumulative effect of pollutants and their influence on microbial characteristics in conventional and modified media bioretention system. The addition of modifiers increased the background content of pollutants in the media, and the accumulation of pollutants in planting soil (PS) and bioretention soil mixing + water treatment residuals (BSM+WTR) was relatively higher after the simulated rainfall experiment. The accumulation of pollutants led to a decrease in dehydrogenase activity, and an increase in urease and invertase activities. Ten dominant bacterial species at the phylum level were found in all bioretention systems. The relative abundances of the bacteria with good viability under low nutritional conditions decreased, while the species which could live in the pollutant-rich environment increased. The accumulation of pollutants in the bioretention system led to the extinction of some functional microorganisms. The better the effects of modified media on pollutant removal showed, the more obvious effect on the media micro-ecosystem was. To ensure the long-term efficient and stable operation of the modified-media bioretention system, we recommend balancing the pollutant removal efficiency and cumulative effect in modified-media bioretention systems.

Influences of stormwater concentration infiltration on the heavy metal contents of soil in rain gardens.

Many studies have been conducted on water volume reduction and pollutants purification of rain gardens. However, the pollutant variations in rain gardens are rarely explored. Seven soil sampling events were conducted from April 2017 to February 2019 to investigate the influences of stormwater concentration infiltration on soil heavy metals in two rain gardens. The results show that: (1) Cu, Zn, and Cd contents in rain garden soil are greater than those of the control soil. They vary with seasons and are trapped in the top layer of 0-30 cm; (2) Cu, Zn, and Pb exist as iron-manganese oxide combined form (S3), organic bound (S4) and residual forms (S5). However, Cd exists in exchangeable (S1) and carbonate bound (S2) forms, whereas Cr is in the S2, S3, and S4 forms. (3) According to the Soil Environmental Quality Standard in China, rain gardens, running for 8-9 years, are relatively clean and, within level II. However, compared with the background content of Shaanxi Province and the world, they are moderately or even heavily polluted by Cd and Zn and slightly polluted by Cu. It indicates that rain gardens have the risk of heavy metal pollution from stormwater concentration infiltration.

[The Feasibility and Repeatability of Ultrasound Microbubble Angiography in the Determination of Pulmonary Blood Volume in Animal Models].

OBJECTIVE: To investigate the feasibility of measuring pulmonary blood volume (PBV) by ultrasound microbubble angiography, which may provide a feasible method for further detection of PBV changes. METHODS: Ultrasound microbubble angiography was used to calculate the PBV by detecting pulmonary transit time (PTT) and heart rate-normalized pulmonary transit time (nPTT). To evaluate the consensus degree based on the intra-, inter-observer and within-day variation in order to determine the repeatability. The method was used for acute left ventricular dysfunction models to determine the feasibility as well. RESULTS: The Bland-Atlman plots showed good intra-observer, within-day, and inter-observer consistency of measurement results. Application in acute left ventricular dysfunction models showed that, compared with the control, left heart failure models had higher PTT, nPTT and PBV ( P<0.05). CONCLUSION: Detection of PTT/nPTT to calculate PBV by ultrasound microbubble angiography is simple and feasible, it is not easy to produce miscarriage of justice, with good intra- and inter-observer consistency of repeatability test results. The method has certain feasibility.

The proportion, origin and pro-inflammation roles of low density neutrophils in SFTS disease.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is a novel emerging viral infectious disease. We explored the percentage, origins and functional roles of low density neutrophils (LDNs), one of the neutrophils subsets, in SFTS. METHODS: The LDNs and normal density neutrophils (NDNs) from blood of SFTS and normal volunteers which were collected separately. The percentage, origins and the phagocytic capability of SFTS viral (SFTSV) of LDNs were investigated by flow cytometry and real time PCR. The capacity of LDNs to secrete cytokines and to damage endothelial cells was assessed by ELISA and flow cytometry. RESULTS: We observed that the proportion of LDNs increased dramatically compared with the healthy donors and became the dominant circulating neutrophil population in SFTS patients. Interestingly, the NDNs from the normal donors could switch to LDNs under the SFTS environment. Moreover, SFTSV load in LDNs was significantly higher than that of NDNs in the severe SFTS patients. In addition, the LDNs secreted much higher levels of pro-inflammatory cytokines than NDNs in SFTS and could induce endothelial cell injury. CONCLUSION: The NDNs can be converted to LDNs. This conversion mechanism could become the source of LDNs. The LDNs in severe SFTS patient could engulf more SFTSV and exhibit pro-inflammation functions. TRIAL REGISTRATION: The Ethics Committee of Tongji Medical College, Huazhong University of Science and Technology (IORG No: IORG0003571) gave a final APPROVAL for the study.

Right Ventricular Dissipative Energy Loss Detected by Vector Flow Mapping in Children: Characteristics of Normal Values.

OBJECTIVES: The feasible application of vector flow mapping (VFM)-derived right ventricular (RV) energy loss (EL) is lacking. This study was designed to determine reference values of VFM-derived EL within the right ventricle and evaluate potential correlated variables. METHODS: A total of 90 healthy children were enrolled. Velocity vector fields of the intra-RV outflow tract and pulmonary trunk (OP) and RV blood flow were obtained from the parasternal short-axis view and RV focused apical 4-chamber view, respectively. RV-EL and OP-EL values during diastole and systole were calculated using VFM analysis. The potential relationships between demographic and echocardiographic parameters and the dissipative EL were also identified. RESULTS: Mean subject age was 8.99 ± 5.35 years. The median (interquartile range) values were 8.82 (5.47-14.30) W/m for RV diastolic EL, 3.17 (2.11-5.54) W/m for RV systolic EL, 18.82 (13.93-24.92) W/m for OP diastolic EL, and 29.88 (20.62-40.78) W/m for OP systolic EL, respectively. The dissipative EL values were negatively correlated with age and RV global strain, and positively correlated with heart rate and RV Tei index. Multivariate analysis showed that age was the primary independent predictor of these 4 types of EL, while heart rate and strain were contributors of the RV diastolic EL and OP systolic EL. CONCLUSIONS: The present study initially validated the application of vector flow mapping-derived EL analysis in right ventricle and established reference values for the future assessment of children with cardiopulmonary disease. Age, heart rate, and strain were independent variables correlated with the dissipative EL.

Fistula occlusion and ligation for a giant right coronary artery aneurysm concurrent with right atrial fistula: a case report.

BACKGROUND: Coronary artery aneurysms in most cases require surgical treatment once diagnosed. Lifelong anticoagulation is often needed after surgery. We herein describe a 55-year-old man who was asymptomatic and diagnosed with right giant coronary artery aneurysm combined with right atrial fistula. CASE PRESENTATION: This is a case of asymptomatic giant right coronary artery aneurysm concurrent with coronary artery fistula. Because the aneurysm was in the distal right posterior descending coronary artery, right coronary artery ligation and fistula occlusion through the right atrium were performed in the absence of cardiopulmonary bypass. The aneurysm was excluded without impacting the myocardial blood supply, and the patient was exempted from lifelong anticoagulation regimen. The follow-up revealed favorable outcomes and the patient's life expectancy was improved. CONCLUSION: Decompression and exclusion without cardiopulmonary bypass can be adopted for distal coronary artery aneurysms that do not involve or only have a limited impact on distal blood supply. This procedure can exempt the patient from the lifelong anticoagulation regimen. In addition, the risk for myocardial ischemia caused by the thrombus in the aneurysm can also be avoided. The whole procedure is comparatively easy to perform.

Modeling the effects of parameter optimization on three bioretention tanks using the HYDRUS-1D model.

The operation effects of bioretention on different tanks were investigated through tests and simulations. Three layered bioretention tanks, namely, #1, #2, and #3, were selected for intermittent operation tests. The artificial filler layers of the tanks consisted of mixed fillers of fly ash and sand, blast furnace slag, and planting soil. Models were established by using HYDRUS-1D software based on test results. The sensitivity of model parameters was analyzed through Morris screening method. Results showed that return period, thickness of media layer, and solute concentration in the liquid phase were the parameters that significantly influenced the operation effects. The Nash-Sutcliffe efficiency coefficients of the models were greater than 0.85. The simulation results showed that the reduction effects at different inflow loads were better under low loads than under high loads. The comprehensive reduction rate of pollutant load was 5.22% less under high concentrations than under low concentrations. The comprehensive reduction rates of water and pollutant loads were 35.97% and 20.68% greater, correspondingly, in the 1 year return period than in the 10 year return period. The artificial fillers comprising a mixture of fly ash and sand also showed the optimal reduction effects, with comprehensive reduction rates of 69.33% and 83.08% for water and pollutant load, respectively. The reduction effects of water and pollutants for the #1 tank presented an upward trend, whereas those for the #2 tank showed a downward trend given an increase in planting soil thickness. An increase in media thickness enhanced the reduction effects. The media with 60 cm thickness demonstrated the optimal effect.

Vasopressors induce passive pulmonary hypertension by blood redistribution from systemic to pulmonary circulation.

Vasopressors are widely used in resuscitation, ventricular failure, and sepsis, and often induce pulmonary hypertension with undefined mechanisms. We hypothesize that vasopressor-induced pulmonary hypertension is caused by increased pulmonary blood volume and tested this hypothesis in dogs under general anesthesia. In normal hearts (model 1), phenylephrine (2.5 µg/kg/min) transiently increased right but decreased left cardiac output, associated with increased pulmonary blood volume (63% ± 11.8, P = 0.007) and pressures in the left atrium, pulmonary capillary, and pulmonary artery. However, the trans-pulmonary gradient and pulmonary vascular resistance remained stable. These changes were absent after decreasing blood volume or during right cardiac dysfunction to reduce pulmonary blood volume (model 2). During double-ventricle bypass (model 3), phenylephrine (1, 2.5 and 10 µg/kg/min) only slightly induced pulmonary vasoconstriction. Vasopressin (1U and 2U) dose-dependently increased pulmonary artery pressure (52 ± 8.4 and 71 ± 10.3%), but did not cause pulmonary vasoconstriction in normally beating hearts (model 1). Pulmonary artery and left atrial pressures increased during left ventricle dysfunction (model 4), and further increased after phenylephrine injection by 31 ± 5.6 and 43 ± 7.5%, respectively. In conclusion, vasopressors increased blood volume in the lung with minimal pulmonary vasoconstriction. Thus, this pulmonary hypertension is similar to the hemodynamic pattern observed in left heart diseases and is passive, due to redistribution of blood from systemic to pulmonary circulation. Understanding the underlying mechanisms may improve clinical management of patients who are taking vasopressors, especially those with coexisting heart disease.

Genetic variance of transforming growth factor ß2 gene in conotruncal heart defects.

OBJECTIVE: The aim of this study was to evaluate the association between two haplotype-tag single nucleotide polymorphisms (SNPs) (rs6658835 and rs10495098) of TGF-ß2 and conotruncal heart defects (CTDs). METHODS: Two polymorphisms of TGF-ß2 gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) from 259 CTDs patients and 310 control subjects. RESULTS: The association between SNP rs6658835 in TGF-ß2 and CTDs has been found. The frequency of G allele in CTDs patients was significantly higher than that in control subjects (52.7% versus 40.3%, p < 0.001, OR =1.649). CONCLUSION: TGF-ß2 gene polymorphisms may serve as a novel genetic marker for the risk of CTDs.