Integrated Hfq-interacting RNAome and transcriptomic analysis reveals complex regulatory networks of nitrogen fixation in root-associated Pseudomonas stutzeri A1501.

The RNA chaperone Hfq acts as a global regulator of numerous biological processes, such as carbon/nitrogen metabolism and environmental adaptation in plant-associated diazotrophs; however, its target RNAs and the mechanisms underlying nitrogen fixation remain largely unknown. Here, we used enhanced UV cross-linking immunoprecipitation coupled with high-throughput sequencing to identify hundreds of Hfq-binding RNAs probably involved in nitrogen fixation, carbon substrate utilization, biofilm formation, and other functions. Collectively, these processes endow strain A1501 with the requisite capabilities to thrive in the highly competitive rhizosphere. Our findings revealed a previously uncharted landscape of Hfq target genes. Notable among these is nifM, encoding an isomerase necessary for nitrogenase reductase solubility; amtB, encoding an ammonium transporter; oprB, encoding a carbohydrate porin; and cheZ, encoding a chemotaxis protein. Furthermore, we identified more than 100 genes of unknown function, which expands the potential direct regulatory targets of Hfq in diazotrophs. Our data showed that Hfq directly interacts with the mRNA of regulatory proteins (RsmA, AlgU, and NifA), regulatory ncRNA RsmY, and other potential targets, thus revealing the mechanistic links in nitrogen fixation and other metabolic pathways. IMPORTANCE: Numerous experimental approaches often face challenges in distinguishing between direct and indirect effects of Hfq-mediated regulation. New technologies based on high-throughput sequencing are increasingly providing insight into the global regulation of Hfq in gene expression. Here, enhanced UV cross-linking immunoprecipitation coupled with high-throughput sequencing was employed to identify the Hfq-binding sites and potential targets in the root-associated Pseudomonas stutzeri A1501 and identify hundreds of novel Hfq-binding RNAs that are predicted to be involved in metabolism, environmental adaptation, and nitrogen fixation. In particular, we have shown Hfq interactions with various regulatory proteins' mRNA and their potential targets at the posttranscriptional level. This study not only enhances our understanding of Hfq regulation but, importantly, also provides a framework for addressing integrated regulatory network underlying root-associated nitrogen fixation.

Metabolic adaptations in pressure overload hypertrophic heart.

This review article offers a detailed examination of metabolic adaptations in pressure overload hypertrophic hearts, a condition that plays a pivotal role in the progression of heart failure with preserved ejection fraction (HFpEF) to heart failure with reduced ejection fraction (HFrEF). The paper delves into the complex interplay between various metabolic pathways, including glucose metabolism, fatty acid metabolism, branched-chain amino acid metabolism, and ketone body metabolism. In-depth insights into the shifts in substrate utilization, the role of different transporter proteins, and the potential impact of hypoxia-induced injuries are discussed. Furthermore, potential therapeutic targets and strategies that could minimize myocardial injury and promote cardiac recovery in the context of pressure overload hypertrophy (POH) are examined. This work aims to contribute to a better understanding of metabolic adaptations in POH, highlighting the need for further research on potential therapeutic applications.

The Gß-like protein Bcgbl1 regulates development and pathogenicity of the gray mold Botrytis cinerea via modulating two MAP kinase signaling pathways.

The fungal Gß-like protein has been reported to be involved in a variety of biological processes, such as mycelial growth, differentiation, conidiation, stress responses and infection. However, molecular mechanisms of the Gß-like protein in regulating fungal development and pathogenicity are largely unknown. Here, we show that the Gß-like protein gene Bcgbl1 in the gray mold fungus Botrytis cinerea plays a pivotal role in development and pathogenicity by regulating the mitogen-activated protein (MAP) kinases signaling pathways. The Bcgbl1 deletion mutants were defective in mycelial growth, sclerotial formation, conidiation, macroconidial morphogenesis, plant adhesion, and formation of infection cushions and appressorium-like structures, resulting in a complete loss of pathogenicity. Bcgbl1 interacted with BcSte50, the adapter protein of the cascade of MAP kinase (MAPK). Bcgbl1 mutants had reduced phosphorylation levels of two MAPKs, namely Bmp1 and Bmp3, thereby reducing infection. However, deletion of Bcgbl1 did not affect the intracellular cAMP level, and exogenous cAMP could not restore the defects. Moreover, Bcgbl1 mutants exhibited defects in cell wall integrity and oxidative stress tolerance. Transcriptional profiling revealed that Bcgbl1 plays a global role in regulation of gene expression upon hydrophobic surface induction. We further uncovered that three target genes encoding the hydrophobic surface binding proteins (HsbAs) contributed to the adhesion and virulence of B. cinerea. Overall, these findings suggest that Bcgbl1 had multiple functions and provided new insights for deciphering the Bcgbl1-mediated network for regulating development and pathogenicity of B. cinerea.

Sclerotinia sclerotiorum Agglutinin Modulates Sclerotial Development, Pathogenicity and Response to Abiotic and Biotic Stresses in Different Manners.

Sclerotinia sclerotiorum is an important plant pathogenic fungus of many crops. Our previous study identified the S. sclerotiorum agglutinin (SSA) that can be partially degraded by the serine protease CmSp1 from the mycoparasite Coniothyrium minitans. However, the biological functions of SSA in the pathogenicity of S. sclerotiorum and in its response to infection by C. minitans, as well as to environmental stresses, remain unknown. In this study, SSA disruption and complementary mutants were generated for characterization of its biological functions. Both the wild-type (WT) of S. sclerotiorum and the mutants were compared for growth and sclerotial formation on potato dextrose agar (PDA) and autoclaved carrot slices (ACS), for pathogenicity on oilseed rape, as well as for susceptibility to chemical stresses (NaCl, KCl, CaCl2, sorbitol, mannitol, sucrose, sodium dodecyl sulfate, H2O2) and to the mycoparasitism of C. minitans. The disruption mutants (ΔSSA-175, ΔSSA-178, ΔSSA-225) did not differ from the WT and the complementary mutant ΔSSA-178C in mycelial growth. However, compared to the WT and ΔSSA-178C, the disruption mutants formed immature sclerotia on PDA, and produced less but larger sclerotia on ACS; they became less sensitive to the eight investigated chemical stresses, but more aggressive in infecting leaves of oilseed rape, and more susceptible to mycoparasitism by C. minitans. These results suggest that SSA positively regulates sclerotial development and resistance to C. minitans mycoparasitism, but negatively regulates pathogenicity and resistance to chemical stresses.

The toxicity assessment of neorudin in cynomolgus monkeys.

In this study, the toxicity effects on circulatory system and respiratory system, and the acute toxicity test of recombinant neorudin (EPR-hirudin, EH) in cynomolgus monkeys were evaluated to provide reference information for clinical studies. Eighteen cynomolgus monkeys were randomly divided into three groups for single intravenous administration of 3, 30 mg/kg EH and normal saline, respectively. The changes of respiratory frequency, respiratory intensity, blood pressure and electrocardiogram before and after administration were recorded. In acute toxicity test, six cynomolgus monkeys were intravenously received EH at a single dose of 171, 257, 385, 578, 867 and 1300 mg/kg respectively. The vital signs, hematology, serum biochemistry, coagulation indexes and electrocardiogram indexes of the animals were determined before administration and on the 7th and 14th day after administration. As the results showed that there were no significant abnormal changes in respiratory frequency, respiratory intensity, blood pressure or electrocardiogram in cynomolgus monkeys after receiving EH at 3 mg/kg and 30 mg/kg, and there was no statistical difference between the treated groups and normal saline group. In the acute toxicity test, no significant abnormalities were observed in vital signs, hematology, serum biochemistry, coagulation indexes and electrocardiogram indexes of six cynomolgus monkeys at day 7 and 14 after EH administration. Furthermore, autopsies of all cynomolgus monkeys showed no abnormalities. The results of toxicokinetics showed that AUClast of the drug increased in proportion to the EH dose in the range of 171-578 mg/kg, and increased in over proportion to the EH dose in the range of 578-1300 mg/kg. The variation of Cmax was basically consistent with AUClast. In a sum, A single intravenous injection of 3 and 30 mg/kg of EH did not affect the circulatory system and respiratory system in cynomolgus monkeys and the maximum tolerated dose of EH in cynomolgus monkey is over 1300 mg/kg (equivalent to 619-1300 times of the proposed clinical equivalent dose).

Mapping of Fatty Aldehydes in the Diabetic Rat Brain Using On-Tissue Chemical Derivatization and Air-Flow-Assisted Desorption Electrospray Ionization-Mass Spectrometry Imaging.

Fatty aldehydes (FALs) are involved in various biological processes, and their abnormal metabolism is related to the occurrence and development of neurological diseases. Because of their low ionization efficiency, methods for in situ detection and mass spectrometry imaging (MSI) analysis of FALs remain underreported. On-tissue chemical tagging of hardly ionizable target analytes with easily ionized moieties can improve ionization efficiency and detection sensitivity in MSI experiments. In this study, an on-tissue chemical derivatization-air-flow-assisted desorption electrospray ionization-MSI method was developed to visualize FALs in the rat brain. The method showed high sensitivity and specificity, allowing the use of in situ high-resolution MS3 to identify FALs. The methodology was applied to investigate the region-specific distribution of FALs in the brains of control and diabetic encephalopathy (DE) rats. In DE rats, FALs were found to be significantly enriched in various brain regions, especially in the cerebral cortex, hippocampus, and amygdala. Thus, increased FAL levels and oxidative stress occurred in a region-dependent manner, which may contribute to cognitive function deficits in DE. In summary, we provide a novel method for the in situ detection of FALs in biological tissues as well as new insights into the potential pathogenesis of DE.

Integrated mass spectrometry imaging reveals spatial-metabolic alteration in diabetic cardiomyopathy and the intervention effects of ferulic acid.

Diabetic cardiomyopathy (DCM) is a metabolic disease and a leading cause of heart failure among people with diabetes. Mass spectrometry imaging (MSI) is a versatile technique capable of combining the molecular specificity of mass spectrometry (MS) with the spatial information of imaging. In this study, we used MSI to visualize metabolites in the rat heart with high spatial resolution and sensitivity. We optimized the air flow-assisted desorption electrospray ionization (AFADESI)-MSI platform to detect a wide range of metabolites, and then used matrix-assisted laser desorption ionization (MALDI)-MSI for increasing metabolic coverage and improving localization resolution. AFADESI-MSI detected 214 and 149 metabolites in positive and negative analyses of rat heart sections, respectively, while MALDI-MSI detected 61 metabolites in negative analysis. Our study revealed the heterogenous metabolic profile of the heart in a DCM model, with over 105 region-specific changes in the levels of a wide range of metabolite classes, including carbohydrates, amino acids, nucleotides, and their derivatives, fatty acids, glycerol phospholipids, carnitines, and metal ions. The repeated oral administration of ferulic acid during 20 weeks significantly improved most of the metabolic disorders in the DCM model. Our findings provide novel insights into the molecular mechanisms underlying DCM and the potential of ferulic acid as a therapeutic agent for treating this condition.

Corrigendum: Case series: Video-assisted minimally invasive cardiac surgery during pregnancy.

[This corrects the article DOI: 10.3389/fmed.2021.781690.].

Effects of two triterpenoids from Nigella sativa seeds on insulin resistance of 3T3-L1 adipocytes.

Insulin resistance (IR) is a physiological abnormality that occurs when insulin fails to activate the signal transduction pathway in target organs. It was found that supplementation of Nigella sativa seeds with oral antidiabetic medicines helps improve blood glucose control by enhanced ß cells activity and alleviation of IR. However, the activities and related mechanisms of phytochemicals from N. sativa seeds have not been thoroughly explored. In this study, the effects of two triterpenoids, 3-O-[ß-D-xylopyranose-(1→3)-α-L-rhamnose-(1→2)-α-L-arabinose]-28-O-[α-L-rhamnose-(1→4)-ß-D-glucopyranose-L-(1→6)-ß-D-glucopyranose]-hederagenin (Hxrarg) and 3-O-[ß-D-xylopyranose-(1→3)-α-L-rhamnose-(1→2)-α-L-arabinose]-hederagenin (Hxra), on IR were studied by 3T3-L1 adipocytes model. The results demonstrated that Hxrarg and Hxra inhibited maturation of 3T3-L1 preadipocytes, dramatically stimulated glucose uptake of IR-3T3-L1 adipocytes, promoted transcription of IRS, AKT, PI-3K, and GLUT4 mRNA. Western Blot results suggested that Hxrarg and Hxra were able to markedly up-regulate expression of p-IRS, p-AKT, PI-3K, and GLUT4 proteins. These findings could provide a basic foundation for the continued development and application of N. sativa in medicine and functional foods.

The Immunomodulatory Effects of Active Ingredients From Nigella sativa in RAW264.7 Cells Through NF-κB/MAPK Signaling Pathways.

Nigella sativa is a valuable herb for its functional compositions in both food and medication. N. sativa seeds can enhance immunity, anti-inflammation and analgesia and hypoglycemia, but most of the related researches are related to volatile oil and extracts, and the activity and mechanism of compounds is not clear. In this study, Ethyl-α-D-galactopyranoside (EG), Methyl-α-D-glucoside (MG), 3-O-[ß-D-xylopyranose-(1 → 3)-α-L-rhamnose-(1 → 2)-α-L-arabinose]-28-O-[α-L-rhamnose-(1 → 4)-ß-D-glucopyranose-L-(1 → 6)-ß-D-glucopyranose]-hederagenin (HXRARG) and 3-O-[ß-D-xylopyranose-(1 → 3)-α-L-rhamnose-(1 → 2)-α-L-arabinose]-hederagenin (HXRA) were isolated and identified from N. sativa seeds. In addition, four compounds could activate NF-κB pathway by promoting the expression of phosphorylation of P65 and IκBα, promoting the phosphorylation of JNK, Erk and P38 to activate MAPK signaling pathway, enhancing the proliferation and phagocytic activity of RAW264.7 cells, and promoting the release of NO, TNF-α and IL-6 on RAW264.7 cell in vitro. The results showed that N. sativa can be used as dietary supplement to enhance immune.

Selenocystine-Derived Label-Free Fluorescent Schiff Base Nanocomplex for siRNA Delivery Synergistically Kills Cancer Cells.

Chemo and siRNA synergic treatments for tumors is a promising new therapeutic trend. Selenocystine, a selenium analog of cysteine, has been considered a potential antitumor agent due to its redox perturbing role. In this study, we developed a nanocarrier for siRNA based on a selenocystine analog engineered polyetherimide and achieved traceable siRNA delivery and the synergic killing of tumor cells. Notably, we applied the label-free Schiff base fluorescence mechanism, which enabled us to trace the siRNA delivery and to monitor the selenocystine analogs' local performance. A novel selenocystine-derived fluorescent Schiff base linker was used to crosslink the polyetherimide, thereby generating a traceable siRNA delivery vehicle with green fluorescence. Moreover, we found that this compound induced tumor cells to undergo senescence. Together with the delivery of a siRNA targeting the anti-apoptotic BCL-xl/w genes in senescent cells, it achieved a synergistic inhibition function by inducing both senescence and apoptosis of tumor cells. Therefore, this study provides insights into the development of label-free probes, prodrugs, and materials towards the synergic strategies for cancer therapy.

Association of Mycoplasma pneumoniae coinfection with adenovirus pneumonia severity in children.

Between the winter of 2018 and the end of 2019, there has been an epidemic of adenovirus infection in southern China, including Zhejiang Province. The number of children suffering from adenovirus pneumonia (AP) has significantly increased. AP can be accompanied by Mycoplasma pneumoniae in children. This study aimed to investigate the association of M. pneumoniae and identify the risk factors for coinfection on hospitalized patients with AP. The patients were classified into two groups by etiologic analysis (single AP and AP with M. pneumoniae coinfection groups). The clinical manifestations, clinical medication, and laboratory and imaging findings of the two groups were compared and analyzed. The coinfection group (n = 125) had a significantly longer duration of fever than the single AP group (n = 171; P = 0.03). Shortness of breath (P = 0.023) and pulmonary imaging findings, such as pulmonary consolidation, atelectasis, pleural effusion, and multilobe lesions (P < 0.05), were more common in the coinfection group. The patients with coinfection had more severe symptoms, significantly longer hospitalization time and an increased proportion of using glucocorticoids and/or immunoglobulin needing oxygen inhalation (P < 0.05). The incidence of AP with M. pneumoniae coinfection is high. The prolonged fever duration and pulmonary imaging findings could be used as prediction factors to predict M. pneumoniae coinfection in children with AP. Patients with AP coinfected with MP may easily develop severe illness. Hence, a reasonable change in the treatment is necessary.

Spatial-resolved metabolomics reveals tissue-specific metabolic reprogramming in diabetic nephropathy by using mass spectrometry imaging.

Detailed knowledge on tissue-specific metabolic reprogramming in diabetic nephropathy (DN) is vital for more accurate understanding the molecular pathological signature and developing novel therapeutic strategies. In the present study, a spatial-resolved metabolomics approach based on air flow-assisted desorption electrospray ionization (AFADESI) and matrix-assisted laser desorption ionization (MALDI) integrated mass spectrometry imaging (MSI) was proposed to investigate tissue-specific metabolic alterations in the kidneys of high-fat diet-fed and streptozotocin (STZ)-treated DN rats and the therapeutic effect of astragaloside IV, a potential anti-diabetic drug, against DN. As a result, a wide range of functional metabolites including sugars, amino acids, nucleotides and their derivatives, fatty acids, phospholipids, sphingolipids, glycerides, carnitine and its derivatives, vitamins, peptides, and metal ions associated with DN were identified and their unique distribution patterns in the rat kidney were visualized with high chemical specificity and high spatial resolution. These region-specific metabolic disturbances were ameliorated by repeated oral administration of astragaloside IV (100 mg/kg) for 12 weeks. This study provided more comprehensive and detailed information about the tissue-specific metabolic reprogramming and molecular pathological signature in the kidney of diabetic rats. These findings highlighted the promising potential of AFADESI and MALDI integrated MSI based metabolomics approach for application in metabolic kidney diseases.

Spatially Resolved Metabolomics Based on Air-Flow-Assisted Desorption Electrospray Ionization-Mass Spectrometry Imaging Reveals Region-Specific Metabolic Alterations in Diabetic Encephalopathy.

Spatially resolved metabolic profiling of brain is vital for elucidating tissue-specific molecular histology and pathology underlying diabetic encephalopathy (DE). In this study, a spatially resolved metabolomic method based on air-flow-assisted desorption electrospray ionization-mass spectrometry imaging (AFADESI-MSI) was developed for investigating the region-specific metabolic disturbances in the brain of DE model rats induced by a high-fat diet in combination with streptozotocin administration. A total of 19 discriminating metabolites associated with glycolysis and the pentose phosphate pathway (PPP); the glutamate/gamma aminobutyric acid-glutamine cycle and tricarboxylic acid cycle; nucleotide metabolism; lipid metabolism; carnitine homeostasis; and taurine, ascorbic acid, histidine, and choline metabolism were identified and located in the brains of the diabetic rats simultaneously for the first time. The results indicated that increased glycolytic and PPP activity; dysfunction of mitochondrial metabolism; dysregulation of adenosinergic, glutamatergic, dopaminergic, cholinergic, and histaminergic systems; disorder of osmotic regulation and antioxidant system; and disorder of lipid metabolism occur in a region-specific fashion in the brains of DE rats. Thus, this study provides valuable information regarding the molecular pathological signature of DE. These findings also underline the high potential of AFADESI-MSI for applications in various central nervous system diseases.

Effect of High-Flow Nasal Cannula Oxygen Therapy on Pediatric Patients With Congenital Heart Disease in Procedural Sedation: A Prospective, Randomized Trial.

OBJECTIVES: The study was conducted to compare the outcome of high-flow nasal cannula (HFNC) oxygen therapy with conventional oxygen therapy through a simple oxygen mask for pediatric patients with congenital heart disease during percutaneous intervention while under procedural sedation. DESIGN: Prospective, randomized and controlled trial. SETTING: A Cantonese cardiac center in China. PARTICIPANTS: Two hundred American Society of Anesthesiologists classification II pediatric patients were enrolled from April 25, 2018 to November 28, 2018. INTERVENTIONS: Patients scheduled for percutaneous closure of a heart defect under deep sedation with propofol, midazolam and fentanyl by an anesthesiologist were randomized (1:1) to receive oxygen therapy through a simple oxygen mask or through the HFNC system. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the lowest oxygen saturation (SpO2). Secondary outcomes included the incidence of hypoxia (SpO2 < 90%), requirement for noninvasive respiratory support, change in the gastric antrum area and other adverse events. Blood gas analysis results also were compared. Oxygen therapy through the HFNC system improved the lowest SpO2 (99% [94%-100%]), as compared with the mask group (99% [72%-100%]), p < 0.001. Seven patients out of 99 (7.1%) in the mask group had hypoxia or required bag-mask ventilation, whereas no such patient was reported in the HFNC group, p < 0.001. There were no differences between the groups in terms of gastric distention, procedure length, total propofol dose, atropine use or other complications. CONCLUSION: When compared with simple mask oxygenation, HFNC could reduce the incidence of desaturation, the need for airway assisted ventilation and risk of carbon dioxide retention without causing hemodynamic instability or gastric distention. It is effective for pediatric patients with non-cyanotic congenital heart disease who require procedural sedation.

The clinical significance of spondin 2 eccentric expression in peripheral blood mononuclear cells in bronchial asthma.

BACKGROUND: Bronchial asthma (BA) was a heterogeneous disease characterized by chronic airway inflammation. Spondin 2 (SPON2) was reported to be implicated in the integrin pathway, protein metabolism, and drug-induced lupus erythematosus. The purpose of this study was to evaluate the significance of SPON2 in BA diagnosis and treatment. METHODS: Peripheral blood samples were obtained from 137 BA pediatric patients (61 mild-to-moderate BA and 76 severe BA) and 59 healthy children. Subject's information, clinical indexes, pulmonary ventilation functions were recorded in the two groups. Peripheral blood mononuclear cells (PBMCs) were isolated from patients' samples. qRT-PCR and ELISA assays were employed to examine the levels of SPON2 and inflammatory cytokines, respectively. Pearson's correlation analysis confirmed the association between SPON2 and inflammatory cytokines. Receiver operating characteristic (ROC) analysis was used to evaluate the potentials of SPON2 in terms of BA detection and discriminating against the severity of BA. RESULTS: Bioinformatics analysis showed that SPON2, OLFM4, XIST, and TSIX were significantly upregulated, while KDM5D and RPS4Y1 were reduced in BA. GO analysis verified that these six genes were mainly involved in neutrophil degranulation, neutrophil activation involved in immune response, neutrophil activation, and neutrophil-mediated immunity. After isolating PBMCs, we found that SPON2 was remarkably increased in BA pediatric group compared with healthy children, and the relative levels of SPON2 were related to the severity of BA. The receiver operating characteristic (ROC) analysis revealed the high potentials of SPON2 in BA diagnosis (AUC was 0.8080) and severity distinctions (AUCs were 0.7341 and 0.8541, respectively). Also, we found that there were significant differences in fractional exhaled nitric oxide (FeNO), forced expiratory volume in 1 s (FEV1)%, FEV1/ forced vital capacity (FVC)%, immunoglobulin E (IgE), serum eosinophils, and serum neutrophils between mild-to-moderate BA group and severe BA group. Finally, SPON2 was negatively correlated with IL-12 while positively associated with IL-4, IL-13, and IL-17A. CONCLUSIONS: SPON2 was a viable biomarker for diagnosing and degree of severity in BA, providing more insight into exploring BA and treatment's pathogenesis.

Case Series: Video-Assisted Minimally Invasive Cardiac Surgery During Pregnancy.

Surgical intervention is expected to improve maternal outcomes in pregnant patients with heart disease once the conservative treatment fails. For pregnant patients with heart disease, the risk of cardiac surgery under cardiopulmonary bypass (CPB) must be balanced due to the high fetal loss. The video-assisted minimally invasive cardiac surgery (MICS) has been progressively applied and shows advantages in non-pregnant patients over the years. We present five cases of pregnant women who underwent a video-assisted minimally invasive surgical approach for cardiac surgery and the management strategies. In conclusion, the video-assisted MICS is feasible and safe to pregnant patients, with good maternal and fetal outcomes under the multidisciplinary assessment and management.

Revising ventricular septal defect residual shunts without aortic re-cross-clamping: a safe and effective surgical procedure.

BACKGROUND: The conventional approach to revising a residual shunt following ventricular septal defect (VSD) closure is to re-occlude the aorta and repair the residual shunt under cardioplegic arrest. The present study evaluated the safety and effectiveness of a new approach for revising residual shunts following VSD repair without re-occluding the aorta. This approach is known as on beating heart surgery. METHODS: This retrospective study included 80 pediatric patients who underwent surgical closure of a simple VSD. Residual shunts larger than 2 mm were intraoperatively detected by transesophageal echocardiography (TEE) and these patients received immediate reintervention. Of the patients, 37 received on beating heart surgery without aortic cross-clamping (Group A) and 43 patients were operated on with aortic cross-clamping and cardioplegia (Group B). RESULTS: Residual VSD closures were successfully performed in all patients. Group A had significantly shorter aortic cross-clamp times (P<0.0001), significantly shorter CPB times (P<0.01), a lower incidence of prolonged ventilation (>6 hours) (P=0.04), a lower incidence of prolonged intensive care unit (ICU) stay (ICU stay >1 day) (P=0.02), and reduced in-hospital expenses (P<0.0001) compared with Group B. There was no significant difference in the incidence of recurrent residual shunts (P=0.96), prolonged postoperative hospital stay (>5 days) (P=0.24), or the incidence of perioperative complications (P=0.81) between the groups. CONCLUSIONS: On beating heart surgery is a safe and effective approach for the closure of residual VSDs and is significantly associated with a lower incidence of prolonged ventilation, a lower incidence of prolonged ICU stay, and reduced in-hospital expenses.