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BACKGROUND: Primary malignant cardiac tumors are rare in clinic, and surgical resection under cardiopulmonary bypass (CPB) remains the main treatment. The non-physiological perfusion process of CPB leads to contact activation, and the resulting coagulopathy and systemic inflammatory response syndrome (SIRS) are common complications. However, it is difficult to predict the impact of foreign tumor fragments on this pathophysiological process once they enter the bloodstream, making this phenomenon more complex and challenging. CASE PRESENTATION: We report a case of cardiac intimal sarcoma who developed severe coagulopathy and widespread inflammation after excision of massive right ventricular tumor and replacement of tricuspid valve by median sternotomy under CPB. Although the procedure was expected to cause tumor cell necrosis and precautions were taken, uncontrolled massive postoperative bleeding, persistent fever, abnormally elevated inflammatory markers, and recurrent malignant arrhythmias occurred after surgery. In addition to common factors, the most possible underlying mechanism is contact activation triggered following surgical procedure for intimal sarcoma with CPB. CONCLUSION: Patients with intracardiac malignant tumors are at a high risk for serious contact activation during CPB. Preventive application of comprehensive anti-inflammatory measures such as drugs and adsorptive CPB technology, as well as point-of-care (POC) monitoring of coagulation status will be helpful for individualized guidance and optimization of CPB management, and improvement of patient prognosis.
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Trastornos de la Coagulación Sanguínea , Sarcoma , Humanos , Puente Cardiopulmonar/efectos adversos , Puente Cardiopulmonar/métodos , Inflamación/etiología , Inflamación/patología , Hemorragia Posoperatoria/prevención & control , Síndrome de Respuesta Inflamatoria Sistémica , Sarcoma/cirugía , Sarcoma/complicacionesRESUMEN
Complications after cardiac surgery with cardiopulmonary bypass (CPB) are associated with increased morbidity and mortality. Early detection and prompt reversion of tissue hypoperfusion during CPB are key factors to reduce organ dysfunction after cardiac surgery. CO2 (carbon dioxide)-derived variables which are easy to assess and routinely available to evaluate the adequacy of macro- and microcirculation may offer important information on the adequacy of the perfusion during CPB. However, since some practical issues remain unsolved in providing a reliable measurement of CO2 removal from the patient, CO2-derived variables are not widely monitoring during CPB. This review aims to demonstrate the basic principles of CO2-derived variables during CPB, the available techniques to assess CO2-derived variables on CPB and the clinically relevant applications.
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Procedimientos Quirúrgicos Cardíacos , Puente Cardiopulmonar , Humanos , Puente Cardiopulmonar/efectos adversos , Puente Cardiopulmonar/métodos , Dióxido de Carbono , Perfusión/métodos , MicrocirculaciónRESUMEN
As to huge solid mediastinal tumor which direct compression or invasion of the superior/inferior vena cava (SVC/IVC), surgical resection remains the main lifesaving treatment. However, it would present formidable anesthetic challenges due to the extremely high risks of cardiorespiratory compromise, drastic hemodynamic fluctuations and death at all perioperative stages. Here, we report a case of huge anterior mediastinal tumor resection combined with SVC replacement under the assistance of venoarterial extracorporeal membrane oxygenation (VA ECMO), and stable hemodynamics were maintained as well as high internal jugular vein pressure being avoided during the operation procedure. He was weaned off ECMO successfully just after surgery and eventually discharged. No signs of postoperatively neurological complications occurred. Therefore, the use of ECMO assistance in huge mediastinal tumor resection combined with SVC replacement is feasible and safe, which may provide the possibility of surgical treatment for such patients and improve outcomes.
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BACKGROUND: Hyperlactatemia (HL) during cardiopulmonary bypass (CPB) is relatively frequent in infants and associates with increased morbidity and mortality. Studies on adults have shown that carbon dioxide production index (VCO2i) during CPB is linked to the occurrence of HL, with 'critical thresholds' for VCO2i reported to be 60 mL/min/m2. However, considering infants have a higher metabolic rate and lower tolerance to hypoxia, the critical threshold of VCO2i in infants cannot be replied to the existing adults' standards. The objective of this study is to investigate the association of VCO2i during CPB and HL, and explore the critical VCO2i threshold during CPB in infants. METHODS: VCO2i predicts hyperlactatemia during cardiopulmonary bypass in pediatric cardiac surgery (pGDP-VCO2i) is a nested case-control study. A cohort of consecutive pediatric patients of less than 3 years of age, undergoing congenital cardiac surgeries between May 2021 and December 2023 in West China Hospital will be enrolled. The VCO2i levels of each patient will be recorded every 5 min during CPB. The primary outcome is the rate of HL. The infants will be divided into two groups based on the presence or not of HL. Pre- and intraoperative factors will be tested for independent association with HL. Then, we will make an analysis, and the critical value of VCO2i will be obtained. The postoperative outcome of patients with or without HL will be compared. DISCUSSION: This will be the first trial to investigate the association of VCO2i during CPB and HL, and explore the critical VCO2i threshold during CPB in pediatrics. The results of this study are expected to lay a foundation for clinical application of goal-directed perfusion (GDP) management strategy, and optimize the perfusion strategy and improve the prognosis of pediatric patients undergoing cardiac surgery. TRIAL REGISTRATION: Chictr.org.cn, ChiCTR2100044296 on 16 March 2021.
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Williams syndrome (WS) is a rare congenital developmental disorder caused by the deletion of between 26 and 28 genes on chromosome 7q11.23. For patients with WS, in view of the particularity of the supravalvular aortic stenosis, choosing appropriate arterial cannula, maintaining higher perfusion pressure as well as strengthening myocardial protection during cardiopulmonary bypass (CPB) is essential to the clinical outcome. Here, we report a child with pulmonary artery valvular stenosis who failed to wean off CPB because of malignant arrhythmias and cardiac insufficiency after surgical correction of pulmonary valvular stenosis. With the assistance of extracorporeal membrane oxygenation (ECMO), emergency cardiac catheterization revealed supravalvular aortic stenosis (SVAS), which suggests a suspected missed diagnosis of WS. Finally, under the support of ECMO, the cardiac function gradually returned to normal, and the child was discharged 23 days after surgery.
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Estenosis Aórtica Supravalvular , Estenosis de la Válvula Pulmonar , Síndrome de Williams , Niño , Humanos , Lactante , Síndrome de Williams/complicaciones , Síndrome de Williams/diagnóstico , Síndrome de Williams/cirugía , Estenosis Aórtica Supravalvular/diagnóstico , Estenosis Aórtica Supravalvular/cirugía , Puente Cardiopulmonar , Constricción Patológica , Diagnóstico Erróneo , Estenosis de la Válvula Pulmonar/diagnóstico , Estenosis de la Válvula Pulmonar/cirugíaRESUMEN
BACKGROUND: Multiple doses of dexamethasone and tranexamic acid can inhibit postoperative inflammation and reduce fibrinolysis and perioperative blood loss in total knee arthroplasty. In this single-center, double-blind, randomized clinical trial, the aim was to investigate whether applying a tourniquet to patients on dexamethasone and tranexamic acid could further reduce perioperative blood loss. MATERIALS AND METHODS: Patients who underwent cemented total knee arthroplasty at our hospital were randomized to receive a tourniquet (n = 71) or not (n = 70) during the procedure. All patients received multiple doses of dexamethasone and tranexamic acid perioperatively. The primary outcome was perioperative blood loss, while secondary outcomes were surgery duration, postoperative laboratory indices of inflammation and fibrinolysis, range of knee motion, VAS pain score, knee circumference, knee swelling rate, homologous transfusion, albumin use, and complications. RESULTS: Using a tourniquet was associated with significantly lower intraoperative blood loss (P < 0.001) and total blood loss (P = 0.007) as well as significantly shorter surgery duration (P < 0.001). In contrast, the tourniquet did not significantly affect hidden blood loss, postoperative inflammation or fibrinolysis, range of knee motion, VAS pain score, knee circumference, knee swelling rate, homologous transfusion, albumin use, or complications. CONCLUSIONS: The results of this randomized clinical trial demonstrate that applying a tourniquet during cemented total knee arthroplasty to patients receiving multiple doses of dexamethasone and tranexamic acid can further reduce perioperative blood loss without increasing the risk of inflammation, fibrinolysis, or other complications. Thus, it is advised to use tourniquets combined with dexamethasone and tranexamic acid to reduce perioperative blood loss and avoid tourniquet-related adverse events. LEVEL OF EVIDENCE: Therapeutic Level I. Trial registration Chinese Clinical Trail Registry, ChiCTR2200060567. Registered 5 June 2022-retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=171291.
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Antifibrinolíticos , Artritis , Ácido Tranexámico , Humanos , Ácido Tranexámico/uso terapéutico , Pérdida de Sangre Quirúrgica/prevención & control , Torniquetes/efectos adversos , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Artritis/etiología , Albúminas , Dexametasona , Dolor/etiología , Antifibrinolíticos/efectos adversosRESUMEN
Ginger (Zingiber officinale Roscoe) is a highly important commercial crop in China, which is widely cultivated for its medicinal and nutritional qualities. Fengtou ginger is a variety mainly grown in Central China. From June to September of 2021, leaf yellow spot symptoms were observed on ginger plants var. Fengtou in commercial fields, localized in Laifeng county (29.37ãN, 109.31ãE), Hubei Province, China. Early symptoms were small yellow spots (approximately 0.2 cm) on leaves, but these spots gradually expanded, and the middle turn brown. The incidence of yellow spot on plants was 15% to 35%. To identify the causal agent of the disease, 15 symptomatic leaves were collected on from plants in the field. From each ginger leaf, small fragments (2 to 4 mm) were cut from the margin of the lesions and surface disinfected with 75% ethanol and 2% sodium hypochlorite for 30 s and 60 s, respectively, and rinsed three times with sterile water (Zhong et al. 2022). The disinfected small fragments were placed on Rose Bengal Agar medium at 25 â. After 3 to 5 days of incubation, a total of 11 isolates from leaf samples were obtained, of which 8 showed a radial mycelial growth that was grayish and then darkened. Conidiophores were brown and branched. Conidia were multicellular, obclavate to obpyriform within 9.1-22.6 µm (average 14.3 µm) in length and 6.0-13.5 µm (average 7.9 µm) in width (n=30). The isolates were identified as Alternaria sp. according to their morphological characteristics (Simmons 2007). For further molecular identification, genomic DNAs of two representative isolates (isolate 1 and isolate 4) were extracted and amplificated using a set of primers ITS1/ITS4 (White et al. 1990), RPB2-5F/RPB2-7R (Liu et al. 1999) and gpd1/gpd2 (Berbee et al. 1999), for the internal transcribed spacer (ITS)-rDNA region, partial RNA polymerase II largest subunit (RPB2), and Glyceraldehyde 3-phosphate (GADPH), respectively. The sequences were submitted to GenBank with submission Nos. OM701795 and OM701794 for ITS-rDNA; OM864662 and OM864663 for RPB2; OM864664 and OM864665 for the GADPH gene. A BLAST analysis in GenBank showed 100% identity with A. alternata for ITS (GenBank No. MN907440), RPB2 (GenBank No. KP057228) and GADPH (GenBank No. MK637444), respectively. A pathogenicity test was performed on potted healthy plants of ginger var. Fengtou of 2.5-month-old in a greenhouse. A total of five plants were sprayed with a conidial suspension (105 spores/mL) of each isolate on leaves until runoff (3 to 5 ml per plant) occurred. Five plants were sprayed with sterile water. The plants were grown in a greenhouse at 25 â. Eight days after inoculation, the symptoms similar to diseased leaves in the field appeared on the inoculated leaves, while the controls remained healthy. The fugus re-isolated from infected tissues was morphologically and molecularly identical to the original isolates of A. alternata, which fulfill the Koch's postulates. To our knowledge, this is the first report of A. alternata causing yellow spot on ginger in China. The work will be beneficial to develop effective management methods for preventing and treating this disease and avoid yield and economic loss of ginger in China.
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BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is increasingly used in patients undergoing complex thoracic surgical procedures. However, studies reporting the clinical outcomes of these patients are limited to case reports, without real consensus. Our aim was to evaluate the perioperative use of ECMO as respiratory and/or circulatory support in thoracic surgery: indications, benefits, and perioperative management. METHODS: Between May 2013 and December 2018, we reviewed the clinical data of 15 patients (11 males and 4 females; mean age: 47 years old; range, 25-73 years) undergoing ECMO-assisted thoracic surgery in our hospital. RESULTS: Of the 15 patients, 10 cases received peripheral veno-arterial (VA) ECMO and five cases received veno-venous (VV) ECMO. Indications for ECMO were pulmonary transplantation with hard-to-maintain oxygenation (n = 5), traumatic main bronchial rupture (n = 2), traumatic lung injury (n = 1), airway tumor leading to severe airway stenosis (n = 2), huge thoracic mass infiltrated vena cava (n = 5). The ECMO duration was 1-51 hours. All patients were successfully extubated and weaned from ECMO postoperatively. The main complications were hemorrhage (26.7%), infection (33.3%), acute hepatic dysfunction (33.3%), and venous thrombosis (26.7%). There was only one hospital death and postoperative one-year survival rate was 86%. CONCLUSION: Our experience indicates that ECMO is a feasible method for complex trachea-bronchial surgery, huge thoracic mass excision and lung transplantation, and the ECMO-related risks may be justified. With further accumulation of experience with ECMO, a more sophisticated protocol for management of critical airway or heart failure problems in thoracic surgeries can be derived.
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Oxigenación por Membrana Extracorpórea , Trasplante de Pulmón , Procedimientos Quirúrgicos Torácicos , Adulto , Anciano , Oxigenación por Membrana Extracorpórea/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Torácicos/métodosRESUMEN
Silicon nitride (SiN) mechanical resonators with high quality mechanical properties are attractive for fundamental research and applications. However, it is challenging to maintain these mechanical properties while achieving strong coupling to an electrical circuit for efficient on-chip integration. Here, we present a SiN drum resonator covered with an aluminum thin film, enabling large capacitive coupling to a suspended top-gate. Implementing the full electrical measurement scheme, we demonstrate a high quality factor â¼104 (comparable to that of bare drums at room temperature) and present our ability to detect â¼10 mechanical modes at low temperature. The drum resonator is also coupled to a microwave cavity, so that we can perform optomechanical sideband pumping with a fairly good coupling strength G and demonstrate mechanical parametric amplification. This SiN drum resonator design provides efficient electrical integration and exhibits promising features for exploring mode coupling and signal processing.
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Chitosanase hydrolyzes ß-(1,4)-linked glycosidic bonds are used in chitosan chains to release oligosaccharide mixtures. Here, we cloned and expressed a cold-adapted chitosanase (CDA, Genbank: MW094131) using multi-copy expression plasmids (CDA1/2/3/4) in Pichia pastoris. We identified elevated CDA expression levels in multi-copy strains, with strain PCDA4 selected for high-density fermentation and enzyme-activity studies. The high-density fermentation approach generated a CDA yield of 20014.8 U/mL, with temperature and pH optimization experiments revealing the highest CDA activity at 20 °C and 5.0, respectively. CDA was stable at 10 °C and 20 °C. Thus, CDA could be used at low temperatures. CDA was then displayed on P. pastoris using multi-copy expression plasmids. Then, multi-copy strains were constructed and labelled as PCDA(1-3)-AGα1. Further studies showed that the expression of CDA(1-3)-AGα1 in multi-copy strains was increased, and that strain PCDA3-AGα1 was chosen for high-density fermentation and enzyme activity studies. By using a multi-copy expression and high-density fermentation approach, we observed CDA-AGα1 expression yields of 102415 U/g dry cell weight. These data showed that the displayed CDA exhibited improved thermostability and was more stable over wider temperature and pH ranges than free CDA. In addition, displayed CDA could be reused. Thus, the data showed that displaying enzymes on P. pastoris may have applications in industrial settings.
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Bacillus/genética , Proteínas Bacterianas/genética , Clonación Molecular , Glicósido Hidrolasas/genética , Pichia/genética , Bacillus/metabolismo , Proteínas Bacterianas/metabolismo , Frío , Estabilidad de Enzimas , Fermentación , Expresión Génica , Glicósido Hidrolasas/metabolismo , Pichia/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMEN
Primary arylsulfonamide functional groups feature prominently in diverse pharmaceuticals. However, natural arylsulfonamides are relatively infrequent. In this work, two novel arylsulfonamide natural products were first synthesized, and then a series of novel molecules derived from natural arylsulfonamides were designed and synthesized, and their in vitro cytotoxic activities against A875, HepG2, and MARC145 cell lines were systematically evaluated. The results indicate that some of these arylsulfonamide derivatives exhibit significantly good cytotoxic activity against the tested cell lines compared with the control 5-fluorouracil (5-FU), such as compounds 10l, 10p, 10q, and 10r. In particular, the potential molecule 10q, containing a carbazole moiety, exhibited the highest inhibitory activity against all tested cell lines, with IC50 values of 4.19 ± 0.78, 3.55 ± 0.63, and 2.95 ± 0.78 µg/mL, respectively. This will offer the potential to discover novel drug-like compounds from the sparsely populated area of natural products that can lead to effective anticancer agents.
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AntineoplásicosRESUMEN
BACKGROUND: In patients of chronic thromboembolic pulmonary hypertension undergoing pulmonary endarterectomy, veno-arterial extracorporeal membrane oxygenation (VA-ECMO) provides full haemodynamic support. However, during a rescue treatment of VA-ECMO for patients with difficulty weaning from cardiopulmonary bypass, a significantly increase left ventricular afterload through retrograde infusion of arterialized blood into the descending aorta may occur. CASE PRESENTATION: We report a 70-year-old man who suffered severe residual pulmonary hypertension following pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension. Preoperative echocardiogram showed a dilated and poorly functioning right ventricle, as well as a small left heart with normal function (TAPES9.6 mm, LVEF64%, average E/E'11.94, lateral E'12.1 cm/s, tricuspid regurgitation velocity 2.5 m/s), while postoperative echocardiography revealed a significant decrease of whole ventricular function on postoperative day 1(TAPES4mm, LVEF28%, average E/E'15, lateral E'6.7 cm/s, tricuspid regurgitation velocity 4.1 m/s), indicating the patient developed severe secondary left ventricular dysfunction on the basis of right ventricular dysfunction, during VA-ECMO support. Then comprehensive measures were adopted, such as down-regulating VA-ECMO flow rate, adjusting respiratory parameters, using vasoactive drugs, as well as prostacyclin. Eventually, the pulmonary hypertension decreased to moderate degree, and the heart function improved gradually. CONCLUSIONS: In the face of severe residual pulmonary hypertension and sencondary left ventricular dysfunction associated with VA-ECMO, comprehensive measures described above may facilitate recovery. ECMO flow titration to maintain relatively low flow rate is very important to not only maintain systemic perfusion, but also reduce left ventricular afterload and ensure pulsatile perfusion of pulmonary artery.
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Endarterectomía/métodos , Oxigenación por Membrana Extracorpórea/métodos , Insuficiencia Cardíaca/complicaciones , Hipertensión Pulmonar/complicaciones , Hipertensión Pulmonar/terapia , Anciano , Insuficiencia Cardíaca/diagnóstico por imagen , Humanos , Masculino , Tomografía Computarizada por Rayos XRESUMEN
Steroids are classes of natural products widely distributed in nature, which have been demonstrated to exhibit broad biological functions, and have also attracted increasing interest from bioorganic and pharmaceutical researches. In order to develop novel chemical entities as potential cytotoxic agents, a series of steroidal isatin conjugations derived from epiandrosterone and androsterone were efficiently prepared and characterized, and all these obtained compounds were screened for their potential cytotoxic activities. The preliminary bioassay indicated that most of the newly synthesized compounds exhibited good cytotoxic activities against human gastric cancer (SGC-7901), melanoma (A875), and hepatocellular liver carcinoma (HepG2) cell lines compared with 5-fluorouracil (5-FU), which might be considered as promising scaffold for further development of potential anticancer agents.
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Androsterona/química , Antineoplásicos Fitogénicos/farmacología , Productos Biológicos/farmacología , Isatina/farmacología , Esteroides/farmacología , Androsterona/análogos & derivados , Antineoplásicos Fitogénicos/síntesis química , Antineoplásicos Fitogénicos/química , Productos Biológicos/síntesis química , Productos Biológicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Isatina/síntesis química , Isatina/química , Estructura Molecular , Esteroides/síntesis química , Esteroides/química , Relación Estructura-ActividadRESUMEN
Malignant hyperthermia is a well-known but potentially lethal disorder which is triggered by volatile anesthetics and depolarizing muscle relaxants. Early diagnosis and treatment could save lives. However, during cardiac surgery, hypothermia and cardiopulmonary bypass make the diagnosis of malignant hyperthermia extremely difficult than other surgeries. We report a case of almost-certain malignant hyperthermia, according to the clinical grading scale, in a patient undergoing on-pump coronary artery bypass grafting surgery. The patient underwent difficult weaning from cardiopulmonary bypass until intra-aortic balloon pump and temporary cardiac pacemaker had been implanted. Although dantrolene and corresponding treatments were administered recently, the patient died 12 days after surgery because of acute kidney failure and cardiac arrest. Therefore, it is important for us to previously recognize some specific signs of malignant hyperthermia during cardiopulmonary bypass to avoid severe outcomes.
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Puente Cardiopulmonar , Dantroleno/administración & dosificación , Hipertermia Maligna , Marcapaso Artificial , Resultado Fatal , Humanos , Masculino , Hipertermia Maligna/tratamiento farmacológico , Hipertermia Maligna/etiología , Hipertermia Maligna/fisiopatología , Persona de Mediana EdadRESUMEN
BACKGROUND AND OBJECTIVE: A multi-discipline cardiac and cardiopulmonary bypass (CPB) team simulation scenario was established to compare three different de-airing approaches dealing with massive air embolism in CPB, so as to formulate a standardized procedure to handle this adverse acute event more proficiently and ensure clinical safety. METHOD: A simulation-based clinical CPB massive air embolism scenario was developed by a cardiac and CPB team. Study Objects: Five licensed perfusionists and five CPB trainees were matched randomly into five pairs. Each pair would simulate the three different de-airing approaches separately as followed: (1) Conventional Method: arterial line filter (ALF) de-airing purge line and oxygenator self-recirculation bypass were used to de-air; (2) Arterial-Venous Loop (A-V Loop) Method: surgeons reconnected the arterial and venous lines to de-air by restoring the original priming A-V loop configuration; (3) Isolation of the ALF Method: this ensures de-bubbling of the CPB circuit, but bypasses the ALF function. Assessment Criteria: (1) Times to recovery (duration of the circulation suspension); (2) Subjective evaluation of skill and non-skill performances. RESULTS: As to times to recovery, the Conventional Method group took 290.6 s ± 36.2, the A-V Loop Method group took 196.8 s ± 52.0 and the Isolation of ALF group took 99.4 s ± 15.1. The statistical difference is significant among the three groups (p<0.01). The subjective evaluation of training performance indicates that this simulation-based training is effective in assessing both skill and non-skill abilities. CONCLUSION: CPB simulation-based training was effective in comparing de-airing strategies and can instruct perfusion practices how to optimize techniques. For well-trained, multi-discipline cardiac teams, the A-V Loop Method is highly efficient and reliable in managing CPB massive air embolism. For cardiac teams that do not have this sophisticated training, the Isolation of ALF Method should be their alternative option.
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Puente Cardiopulmonar/educación , Puente Cardiopulmonar/métodos , Entrenamiento Simulado/métodos , Puente Cardiopulmonar/instrumentación , China , Humanos , Perfusión/instrumentación , Perfusión/métodosAsunto(s)
Procedimientos Quirúrgicos Cardíacos , Objetivos , Humanos , Recién Nacido , Oxígeno , PerfusiónRESUMEN
As one of the three key components of the 'Green Revolution', photoperiod insensitivity is vital for improved adaptation of wheat (Triticum aestivum) cultivars to a wider geographical range. Photoperiod-B1a (Ppd-B1a) is one of the major genes that confers photoperiod insensitivity in 'Green Revolution' varieties, and has made a significant contribution to wheat yield improvement. In this study, we investigated the mechanisms underlying the photoperiod insensitivity of Ppd-B1a alleles from an epigenetic perspective using a combination of bisulfite genomic sequencing, orthologous comparative analysis, association analysis, linkage analysis and gene expression analysis. Based on the study of a large collection of wheat germplasm, we report two methylation haplotypes of Ppd-B1 and demonstrate that the higher methylation haplotype (haplotype a) was associated with increased copy numbers and higher expression levels of the Ppd-B1 gene, earlier heading and photoperiod insensitivity. Furthermore, assessment of the distribution frequency of the different methylation haplotypes suggested that the methylation patterns have undergone selection during the wheat breeding process. Our study suggests that DNA methylation in the regulatory region of the Ppd-B1 alleles, which is closely related to copy number variation, plays a significant role in wheat breeding, to confer photoperiod insensitivity and better adaptation to a wider geographical range.
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Metilación de ADN , Regulación de la Expresión Génica de las Plantas/fisiología , Fotoperiodo , Proteínas de Plantas/metabolismo , Triticum/metabolismo , Alelos , Cruzamiento , Epigénesis Genética , Eliminación de Gen , Haplotipos , Proteínas de Plantas/genética , Triticum/genéticaRESUMEN
This paper is aimed to assess the effects of red blood cell (RBC) transfusion on clinical outcomes in cardiac surgery. Trials were identified by computer searches of the Pubmed, MEDLINE, Cochrane Library (Issue 10, 2012), from January 1980 to October 2012. References in identified trials and review articles were checked and experts contacted to identify any additional trials. The homogeneous randomized controlled trials (RCTs) were analyzed with RevMan 5.1 software. Five trials involving a total of 1,203 patients were identified. The results of meta-analyses showed that restrictive transfusion strategies reduced the risk of receiving a RBC transfusion (MD = - 1.46, 95% CI -1.18(-) -1.1) and the volume of RBCs transfusion (RR = 0.69, 95% CI 0.53-0.89). No significant difference was noted between the two strategies in terms of mortality, adverse events and hospital or intensive care length of stay. Based on the results mentioned above, one can draw a conclusion that restrictive transfusion strategies reduced the risk of receiving RBC transfusion and the volume of RBCs transfused. Restrictive transfusion strategies did not appear to impact on the rate of adverse events and hospital or intensive care length of stay, compared to liberal transfusion strategies.
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Procedimientos Quirúrgicos Cardíacos , Transfusión de Eritrocitos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
As an important part of head protection equipment, research on the material and structural application of helmet liners has always been one of the hotspots in the field of helmets. This paper first discusses common helmet liner materials, including traditional polystyrene, polyethylene, polypropylene, etc., as well as newly emerging anisotropic materials, polymer nanocomposites, etc. Secondly, the design concept of the helmet liner structure is discussed, including the use of a multi-layer structure, the addition of geometric irregular bubbles to enhance the energy absorption effect, and the introduction of new manufacturing processes, such as additive manufacturing technology, to realize the preparation of complex structures. Then, the application of biomimetic structures to helmet liner design is analyzed, such as the design of helmet liner structures with more energy absorption properties based on biological tissue structures. On this basis, we propose extending the concept of bionic structural design to the fusion of plant stalks and animal skeletal structures, and combining additive manufacturing technology to significantly reduce energy loss during elastic yield energy absorption, thus developing a reusable helmet that provides a research direction for future helmet liner materials and structural applications.