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The inadequacy of the existing research in characterizing the atomization performance of the whole atomization field by the local region at nozzle axis hinders the improvement of dust removal performance of a spray system, especially for fan-shaped nozzles with large atomization angle. To solve this inadequacy, 88 measuring points were designed in this study to reveal the spatial distribution characteristics of atomization parameters of a fan-shaped pressure atomization nozzle using a 3D Fiber Phase-Doppler Anemometer. Moreover, the atomization performance and dust removal performance of the whole atomization field under different spray pressures were characterized. The results showed that the spatial distribution of atomization parameters in the axis and radial direction of the nozzle was inhomogeneous. As the axial distance from the nozzle outlet increased, the average droplet size showed a trend of first decreasing and then increasing, the proportion of the droplet of 15-70 µm showed a trend of first increasing and then decreasing, while the average droplet velocity and droplet flux showed a decreasing trend. In addition, the spray orientation was perpendicular to gravity, and the atomization field was parallel to gravity, resulting in a significant difference in the average droplet size between the upper region and the axis. Compared with the upper and lower regions, the atomization effect at the axis was superior, manifested by higher average droplet velocity and droplet flux, indicating that characterizing nozzle atomization performance with atomization parameters at the axis will lead to overestimation. The increase of spray pressure can improve atomization performance and dust removal efficiency to a certain extent, but the improvement effect had a limit. The atomization field can be divided into atomization region, expansion region and contraction region, and the expansion region was considered as an effective dust removal region. These findings provide reference for the design and operation of a spray system.
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BACKGROUND: To explore the efficacy and safety of remimazolam for procedural sedation during ultrasound-guided nerve block administration in patients undergoing abdominal tumor surgery, in order to improve and optimize remimazolam use in procedural sedation and clinical anesthesia. METHODS: The enrolled patients were randomly divided into three groups: 50 patients in the remimazolam group (R group), 50 patients in the dexmedetomidine group (D group), and 50 patients in the midazolam group (M group). Before administering an ultrasound-guided nerve block, all patients received sufentanil AND remimazolam or midazolam or dexmedetomidine. Remimazolam 5 mg was administered intravenously in group R, dexmedetomidine 0.6 µg/kg was administered intravenously in group D, and midazolam 0.025 mg/kg was administered intravenously in group M. Sedation was evaluated by the Modified Observer's Assessment of Alertness and Sedation scale.When the Modified Observer's Alertness/Sedation (MOAA/S) score was ≤ 2, block operation was started. If the target sedation level was not reached, rescue sedatives of remimazolam 2.5 mg may be intravenously given in group R, dexmedetomidine 0.4 µg/kg be intravenously given in group D, 0.01 mg/kg midazolam may be intravenously given in Group M. Hemodynamic indicators (systolic and diastolic blood pressure, heart rate), pulse oxygen saturation, depth of anesthesia (Narcotrend), MOAA/S,and the incidences of hypoxemia, injection pain, bradycardia and requirement for rescue sedatives were monitored and recorded. RESULTS: Compared with the control groups (midazolam and dexmedetomidine groups), the Narcotrend index and MOAA/S decreased more in the remimazolam group (P < 0.01). Compared with the control groups, the incidence of hypoxemia and injection pain was slightly higher in the remimazolam group, but the difference was not statistically significant (P > 0.05). Compared with the dexmedetomidine group, the incidence of bradycardia was significantly lower in the remimazolam group. CONCLUSION: Remimazolam can be used safely for procedural sedation during ultrasound-guided nerve block administration in patients undergoing abdominal tumor surgery. The sedation effect is better than that with either midazolam or dexmedetomidine, and sedation can be achieved quickly without obvious hemodynamic fluctuations. Remimazolam is associated with better heart rate stability, and slightly higher incidences of hypoxemia and injection pain than are midazolam and dexmedetomidine (no statistically significant difference). The higher incidence of hypoxemia with remimazolam may be related to enhanced sufentanil opioid analgesia, and the mechanism of injection pain with remimazolam must be studied further and clarified. TRIAL REGISTRATION: This study was approved by the Ethics Committee of Anhui Provincial Cancer Hospital (Ethical Review 2021, No. 23) and registered at https://www.chictr.org.cn (ChiCTR2000035388). The pre-registration time of this experiment is 09/08/2020, due to ethical committee of the hospital met irregularly,the ethical approval time is 21/06/2021. The recruitment of patients began after the ethical approval (21/06/2021) and registration update (06/07/2021).The study protocol followed the CONSORT guidelines. The study protocol was performed in the relevant guidelines.
Subject(s)
Abdominal Neoplasms , Nerve Block , Humans , Abdominal Neoplasms/surgery , PainABSTRACT
Follistatin-like 1 (Fstl1) protects cardiomyocytes from a broad spectrum of pathologic injuries including myocardial infarction (MI). It is worthy of note that although cardiac Fstl1 is elevated in post-MI microenvironment, its cardioprotective role is still restricted to a limited extent considering the frequency and severity of adverse cardiac remodeling following MI. We therefore propose that intrinsic Fstl1-suppressing microRNA (miRNA) may exist in the heart and its neutralization may further facilitate post-MI recovery. Here, miR-9-5p is predicted as one of the potential Fstl1-targeting miRNAs whose expression is decreased in ischemic myocardium and reversely correlated with Fstl1. Luciferase activity assay further validated Fstl1 as a direct target of miR-9-5p. In addition, forced expression of miR-9-5p in H9c2 cells is concurrent with diminished expression of Fstl1 and vice versa. Importantly, transfection of miR-9-5p mimics in hypoxic H9c2 cells exacerbates cardiac cell death, lactate dehydrogenase release, reactive oxygen species accumulation, and malonyldialdehyde concentration. More importantly, in vivo silencing of miR-9-5p by a specific antagomir in a murine acute MI model effectively preserves post-MI heart function with attenuated fibrosis and inflammatory response. Further studies demonstrated that antagomir treatment stabilizes Fstl1 expression as well as blocks cardiac cell death and reactive oxygen species generation in both ischemia-challenged hearts and hypoxia-treated cardiomyoblasts. Finally, cytoprotection against hypoxic challenge by miR-9-5p inhibitor is partially reversed by knockdown of Fstl1, indicating a novel role of miR-9-5p/Fstl1 axis in survival defense against hypoxic challenge. In summary, these findings identified miR-9-5p as a mediator of hypoxic injury in cardiomyoblasts and miR-9-5p suppression prevents cardiac remodeling after acute MI, providing a potential strategy for early treatment against MI.
Subject(s)
Gene Expression Regulation , MicroRNAs/genetics , Myocardial Infarction/genetics , Myocardial Infarction/pathology , RNA Interference , Ventricular Remodeling/genetics , Adenosine Triphosphate/metabolism , Animals , Apoptosis/genetics , Biomarkers , Disease Models, Animal , Echocardiography , Fibrosis , Follistatin-Related Proteins/genetics , Heart Function Tests , Hypoxia/genetics , Hypoxia/metabolism , Male , Mice , MicroRNAs/administration & dosage , Myocardial Infarction/metabolism , Myocardial Infarction/physiopathology , Myocarditis/genetics , Myocarditis/metabolism , Myocarditis/pathology , Myocarditis/physiopathology , Myocytes, Cardiac/metabolism , Oxidative Stress , RNA, Messenger/geneticsABSTRACT
BACKGROUND: Adding an adjuvant, such as dexmedetomidine or dexamethasone, to a nerve block improves its quality and reduces perioperative opioid consumption. We aimed to compare the effect of dexmedetomidine and dexamethasone as an adjuvant for the erector spinae plane block (ESPB) to control postoperative pain after video-assisted thoracoscopic lobectomy surgery (VATLS). METHODS: Ninety patients, aged 20-65 years who were scheduled to undergo VATLS were enrolled in this trial. The visual analogue scale (VAS) score changes at various time points [waking up in post-anesthesia care unit (PACU) and 2, 4, 6, 8, 12, 24, 48, 72 h after surgery], duration of sensory block, first request to use the patient controlled analgesia (PCA) device, total PCA use, postoperative nausea and vomiting (PONV), rate of rescue analgesia use, and post-surgical hospital stay were recorded. RESULTS: VAS score was lower in the ropivacaine with dexmedetomidine (RM) group at wake up and at postoperative 2, 4, 12, and 24 h. The median duration of sensory blockade was significantly longer in the RM group (P=0.001). First request to use the PCA machine in the RM group was prolonged significantly compared with that in the ropivacaine alone (R) group and ropivacaine with dexamethasone (RS) group (P<0.001). Total PCA use, post-surgical hospital stay, and rate of rescue analgesia use in The RM group were reduced significantly compared with those in the R and RS groups. CONCLUSIONS: Using dexmedetomidine (1 µg/kg), instead of dexamethasone (10 mg), as an adjuvant of ESPB with ropivacaine, prolonged sensory block duration, provided effective acute pain control, and required lesser rescue analgesia and shorter hospital stays.
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Tetralogy of Fallot (TOF) is one of the most severe forms of cyanotic congenital heart disease (CHD) and is also the most common. Previous genome-wide association study (GWAS) and replication studies have suggested that a polymorphism in the neuropilin 1 (NRP1) gene is significantly associated with the risk of TOF. To further confirm the association between the NRP1 polymorphism and the risk of TOF and to identify additional positive functional single-nucleotide polymorphisms (SNPs) for TOF risk, we systematically screened for functional polymorphisms throughout the regulatory and coding regions of the NRP1 gene. A total of 11 functional SNPs in 747 Chinese Han individuals, including 314 TOF patients and 433 healthy controls, were genotyped using the MassARRAY system and GeneScan. The results revealed that the allelic and genotypic frequencies of the NRP1 polymorphism rs2228638 were strongly associated with the risk of TOF (pâ¯=â¯0.002 and 0.001, respectively). To increase the robustness of rs2228638 as a TOF risk SNP, we conducted a meta-analysis that combined published studies and our current case-control study. The meta-analysis showed that the T allele of the NRP1 polymorphism rs2228638 was significantly associated with an increased risk of TOF in the combined population, which included European and Chinese Han individuals [combined pâ¯<â¯0.00001, odds ratio (OR)â¯=â¯1.53, 95% confidence interval (95% CI)â¯=â¯1.35-1.73]. In addition, the association analysis suggested for the first time that there is a strong association between the allele distribution of rs10080 and susceptibility to TOF (pâ¯=â¯0.001). Our data provide further evidence of the association between NRP1 polymorphisms and TOF risk, and suggest that rs2228638 may be an excellent marker for TOF risk in European and Chinese Han populations.
Subject(s)
Neuropilin-1/genetics , Polymorphism, Single Nucleotide , Tetralogy of Fallot/genetics , Alleles , Asian People/genetics , Case-Control Studies , Child , Child, Preschool , China , Computational Biology , Female , Gene Frequency , Genetic Markers , Genetic Predisposition to Disease , Genome-Wide Association Study , Genotype , Haplotypes , Humans , Infant , Linkage Disequilibrium , Male , Neuropilin-1/physiology , RiskABSTRACT
OBJECTIVE: The aim of this study was to compare the quality of lung deflation of a left-sided double-lumen endotracheal tube (DLT) with a bronchial blocker (BB) for one-lung ventilation in video-assisted thoracic surgery (VATS). DESIGN: A prospective, randomized, clinical study. SETTING: A university-affiliated teaching hospital. PARTICIPANTS: Forty-five adult patients undergoing esophageal tumor surgery using VATS with right lung deflation. INTERVENTIONS: Patients were assigned by a computer-generated randomization sequence to either the left-sided DLT or BB group. The correct positioning of the airway device was confirmed using fiberoptic bronchoscopy. MEASUREMENTS AND MAIN RESULTS: The variables assessed included: (1) time required to correctly place the devices and to achieve lung collapse; (2) the number of times the device malpositioned; (3) the quality of lung deflation as rated by the surgeon; (4) blood pressure and heart rate at baseline (T1), immediately before (T2) and after (T3) and 1 minute (T4) after intubation; (5) the number of patients with hypoxemia (SpO2 < 90%) during the one-lung ventilation (OLV) period; and (6) postoperative hoarseness of voice, sore throat, or pulmonary infection. Of the 45 patients approached for the study, 21 patients in the DLT group and 19 patients in the BB group were analyzed. The time required to place the device in the correct position was similar between the 2 groups. The time to achieve right lung collapse in the BB group was significantly longer (mean difference: 3.232, 95% confidence interval [CI]: 1.993-4.471; p = 0.003). The quality of lung collapse, OLV duration, number of patients with device malposition, and hypoxemia in both groups were similar. There were more patients suffering hoarseness (odds ratio [OR]: 4.85, 95% CI: 1.08-21.76; p = 0.034) or sore throat (OR: 4.29, 95% CI: 1.14-16.18; p = 0.030) in the DLT group, while no patients developed postoperative lung infection in either group. Compared to T1, systolic blood pressure (sBP), diastolic BP (dBP), and heart rate (HR) at T2 in both groups were higher (p < 0.05) in the DLT group. Then, compared to T2, sBP and dBP at T3 and T4 and HR at T3 in the DLT group were higher (p < 0.05). CONCLUSIONS: The results of this study showed that BB is an effective alternative for left one-lung ventilation in right VATS, but requires a longer time to achieve complete lung collapse. Moreover, the use of BB caused less hemodynamic perturbation and can reduce postoperative hoarseness and sore throat.
Subject(s)
Bronchoscopy/methods , Intubation, Intratracheal/methods , One-Lung Ventilation/methods , Pulmonary Atelectasis/prevention & control , Thoracic Surgery, Video-Assisted/methods , Aged , Aged, 80 and over , Bronchoscopy/adverse effects , Female , Humans , Intubation, Intratracheal/adverse effects , Male , Middle Aged , One-Lung Ventilation/adverse effects , Prospective Studies , Pulmonary Atelectasis/etiology , Pulmonary Atelectasis/physiopathology , Thoracic Surgery, Video-Assisted/adverse effectsABSTRACT
Cardiac hypertrophy is an adaptive enlargement of the myocardium in response to overload pressure of heart. From abundant studies, a conclusion is drawn that many microRNAs (miRNAs) are associated with cardiac hypertrophy and heart failure. To investigate the role of microRNA-497 (miR-497) in myocardial hypertrophy, two models were established in this study from cell level to integral level. Cardiac hypertrophy was induced by using angiotensin â ¡ (Ang â ¡) in vitro and was created by transverse abdominal aortic constriction (TAC) in vivo. There was a significant decrease expression of miR-497 in cardiac hypertrophy models. Moreover, overexpression of miR-497 inhibited myocardial hypertrophy both in vitro and in vivo without heart function variation. In addition, luciferase reporter assays demonstrated that Sirt4 was a direct target gene of miR-497. Taking together, our study indicates that miR-497 modulates cardiac hypertrophy by targeting Sirt4 and may serve as a potential therapeutic substance in the course.
Subject(s)
Cardiomegaly/genetics , MicroRNAs/physiology , Mitochondrial Proteins/genetics , Sirtuins/genetics , Animals , Animals, Newborn , Cells, Cultured , Disease Models, Animal , Gene Expression Regulation, Enzymologic , Mice , Mice, Inbred C57BL , Mitochondrial Proteins/metabolism , Myocardium/metabolism , Myocardium/pathology , Myocytes, Cardiac/metabolism , Sirtuins/metabolismABSTRACT
Respiratory droplet characteristics are key to determine the droplet-borne pathogen transmission, which provide scientific basis for formulating the disease prevention from droplet transmission and control measures. Through studying the data information from existing documents, this paper gives the respiratory droplet characteristics, like size, concentration, velocity, etc. Meanwhile, droplet evaporation, droplet-borne pathogen activity and their transmission are discussed. The droplet size is no significant difference with human health level, gender and age. The size of droplets produced by health people is between 0.1 and 10 µm, it produced by patients is between 0.05 and 10 µm, and the patients' droplet concentration is higher. The coughed droplet concentrations change with the size into a peak rule. The velocity of the cough droplets is the biggest, the range of 10 to 25m/s, the transmission distance is more than 2m.
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Continuous time random walks impose random waiting times between particle jumps. This paper computes the fractal dimensions of their process limits, which represent particle traces in anomalous diffusion.
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This paper is concerned with sample path properties of anisotropic Gaussian random fields. We establish Fernique-type inequalities and utilize them to study the global and local moduli of continuity for anisotropic Gaussian random fields. Applications to fractional Brownian sheets and to the solutions of stochastic partial differential equations are investigated.
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Elder abuse in long-term care has become a very important public health concern. Recent estimates of elder abuse prevalence are in the range of 2% to 10% (Lachs & Pillemer, 2004), and current changes in population structure indicate a potential for an upward trend in prevalence (Malley-Morrison, Nolido, & Chawla, 2006; Post et al., 2006). More than 20 years ago, Karl Pillemer called for sociological research on patient maltreatment in nursing homes and provided an overview model for the conduct of such research (Pillemer, 1988). The research literature since then has not provided the definitive model to account for patient maltreatment that Pillemer hoped for. Instead, it has produced a laundry list of risk factors that includes the patient's functional disability, cognitive impairment, social isolation, age, race, income, family background, life events, dementia, and depression (Dyer, Pavlik, Murphy, & Hyman, 2000; Lachs & Pillemer, 2004; Lachs,Williams, Obrien, Hurst, & Horwitz, 1997; Pavlik, Hyman, Festa, & Dyer, 2001; Schofield & Mishra, 2003). However, no theory exists to place these factors in a causal structure that relates the factors to each other and to whether abuse occurs. This study is a first step in that direction. Nine hypotheses were generated focusing on the effects of two dimensions of impairment--(a) physical and cognitive and (b) age and behavior problems--on susceptibility to abuse among elderly in long-term care.The relationships between factors and from factors to susceptibility to abuse are specified in a structural equation model where "susceptibility to abuse," "physical impairment," and "cognitive impairment" are latent variables, and behavior problems and age are directly measured.