ABSTRACT
BACKGROUND: The number of patients with advanced cancer is rapidly increasing, and the subgroup of this population with low socioeconomic status has suffered more disease burden than others. However, there is no recent qualitative synthesis of primary research studies into advanced cancer patients with low socioeconomic status. OBJECTIVE: To synthesise qualitative research findings into advanced cancer patients' experiences with low socioeconomic status, and then to help provide targeted and effective strategies to improve their quality of life. DESIGN: A systematic review and meta-synthesis of qualitative evidence (PROSPERO: CRD42021250423). DATA SOURCES: PubMed, Web of Science Core Collection (ISI Web of Science), Cochrane Library, Embase, OVID LWW, CINAHL Complete (EBSCO), PsycINFO (EBSCO) and MEDLINE (ISI Web of Science), China National Knowledge Infrastructure (CNKI), WangFang, and Vip databases were systematically searched from their original dates to July 2022. Qualitative data were appraised using the Joanna Briggs Institute (JBI) qualitative assessment. FINDINGS: The findings were synthesised into the following three analytical themes: (1) multi-dimensional disease distresses; (2) barriers in coping with disease distresses; and (3) strategies for dealing with disease distresses. CONCLUSIONS: Patients with advanced cancer with low socioeconomic status experienced complicated and interactional distresses, unique life barriers, and a wide range of adaptation strategies. These findings will provide a comprehensive perspective to promote individual-centred health care systems and services to help these vulnerable people deal with the challenges of disease and improve their quality of life.
Subject(s)
Neoplasms , Quality of Life , Humans , Low Socioeconomic Status , Qualitative Research , Cost of IllnessABSTRACT
BACKGROUND: The objective is to investigate whether calculating the PPI (Pulse Pressure Index) and the RRI (Renal Resistive Index) using routinely collected Duplex ultrasound waveforms data obtained from the aorta and renal artery correlates and predicts renal function, and determine whether RRI is affected by the presence of a renal artery stenosis. METHODS: The records of 965 patients were evaluated. The RRI or pulsatility index of the aorta, renal artery, hilum, cortex, and medulla were measured with concurrent glomerular filtration rate GFR, Cr, PPI, and HR measurements, among which 75 patients had a 24-hour urine measured for CrCl, and 32 patients had aortic pulse pressure index (API) calculated from the central aortic pressure measured with applanation tonometry. The propagation of the pulsatility was evaluated by Analysis of Variance (ANOVA). The correlation coefficient (r) and the linear regression coefficient of determination R-squared (R2) were determined. The effects of a renal artery stenosis were evaluated with a paired t-Test comparing the RRI in 192 patients where only one side had a renal artery stenosis greater than 60%. RESULTS: The pulsatility indexes and RRIs progressively decreases and are statistically distinct by ANOVA from the aorta to the renal cortex (P = 7.26 × 10-125). CrCl correlates with the PPI, cortex RRI and medulla RRI with r equal to -0.34, -0.23 and -0.42 (P < 0.05). GFR correlates with the PPI, cortex RRI and medulla RRI with r equal to -0.15, -0.12, and -0.20 (P < 0.0001). Cr correlates with the PPI, cortex RRI and medulla RRI with r equal to 0.09, 0.12, and 0.14 (P < 0.005). The CrCl, GFR and Cr were not statistically correlated with the HR. On univariate and multivariate analysis, the R2 predictive value for PPI, cortex RRI and medulla RRI for CrCl, GFR and Cr were all less than 0.2 (P < 0.05). The cortex and medulla RRI were correlated with the API with r = 0.63 (P < 0.001). The R2 predictive value of the PPI for the cortex and medulla RRI was 0.41 and 0.28 (P < 0.001), respectively. On paired t-Test analysis renal artery stenosis had no effect on the RRI (P = 0.78). CONCLUSIONS: The RRI is calculated based on velocity waveform propagation where pulsatility slowly decreases in a series of elastic vessels. While CrCl, GFR and Cr do correlate with the PPI, cortex RRI and medulla RRI, the R2 coefficient of determination for these correlations demonstrate that they are poor predictors of renal function. Renal artery stenosis did not have any effect on the RRI.
Subject(s)
Renal Artery Obstruction , Renal Artery , Humans , Renal Artery/diagnostic imaging , Renal Artery Obstruction/diagnostic imaging , Treatment Outcome , Glomerular Filtration Rate , Aorta/diagnostic imaging , Kidney/diagnostic imaging , Kidney/blood supply , Vascular ResistanceABSTRACT
Glioma is the most common type of brain cancer. Chemotherapy combination with surgery and radiotherapy is a standard treatment for patients. Although there are many advances in glioma therapy, the prognosis of glioma patients has not significantly been improved over the past decades. Hence, there is still an urgent need to develop a new therapy to treat glioma. Cell viability was assessed by CellTiter Blue assay; flow cytometry (FCM) was used for detecting cell apoptosis; ROS detection was detected by ROS Assay; H2O2 detection was performed by hydrogen peroxide detection kits; real-time PCR and WB were used to determine gene expression. Using the glioma cell line U251 and U87, we investigated a possible combination inhibitory effect includes metformin and cold atmospheric plasma (CAP). The combination treatment showed a synergistic inhibitory effect on cell viability, significantly inducing cell apoptosis. Furthermore, we also found H2O2 produced by CAP has an important role in the synergistic inhibitory effect, eliminating H2O2 with catalase reversed the synergistic inhibitory effect. In addition, the transcript and protein levels of c-FOS were robustly increased after co-treated with metformin and CAP. Taken together, we propose that pre-treatment of glioma cells with metformin sensitize tumor cells to CAP, which may serve as a potential therapeutic strategy for glioma.
Subject(s)
Brain Neoplasms , Glioma , Metformin , Plasma Gases , Apoptosis/drug effects , Brain Neoplasms/drug therapy , Brain Neoplasms/pathology , Brain Neoplasms/therapy , Cell Death/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Glioma/drug therapy , Glioma/pathology , Glioma/therapy , Humans , Hydrogen Peroxide , Metformin/pharmacology , Plasma Gases/pharmacologyABSTRACT
BACKGROUND: To study the effect of dexmedetomidine (Dex) on the expression of Neuroglobin (Ngb) and postoperative cognitive function in elderly patients undergoing minimally invasive coronary artery bypass surgery. METHODS: Forty patients, who underwent elective minimally invasive off-pump coronary artery bypass grafting in our hospital from January 2018 to December 2019, were randomly divided into the Dex group (N = 20) and control group (N = 20). Venous blood samples were taken to determine the expression level of Ngb in both groups. Mini mental status examination (MMSE) was used to detect the cognitive function of patients. RESULTS: The expression level of Ngb in the Dex group was significantly higher than that in the control group at 6h after one-lung ventilation and postoperative 24h (P < .01). The MMSE score of the Dex group was significantly higher than the control group at postoperative 7 days and postoperative 30 days (P < .01). Although with no statistical significance, the MMSE score of the Dex group was higher than the control group at postoperative 90 days (P > .05). The incidence of postoperative cognitive dysfunction (POCD) in the Dex group was significantly lower than that in the control group at postoperative 7 days and postoperative 30 days (P < .05). CONCLUSION: Dex used in elderly patients undergoing minimally invasive coronary artery bypass graft surgery can effectively increase the expression level of Ngb and reduce the incidence of POCD.
Subject(s)
Coronary Artery Bypass/adverse effects , Coronary Artery Disease/surgery , Dexmedetomidine/therapeutic use , Elective Surgical Procedures/adverse effects , Minimally Invasive Surgical Procedures/adverse effects , Neuroglobin/biosynthesis , Postoperative Cognitive Complications/blood , Aged , Analgesics, Non-Narcotic/therapeutic use , China/epidemiology , Cognition/drug effects , Cognition/physiology , Female , Follow-Up Studies , Humans , Incidence , Male , Neuroglobin/blood , Postoperative Cognitive Complications/epidemiology , Postoperative Cognitive Complications/prevention & control , Retrospective StudiesABSTRACT
AIM: To psychometrically test the Chinese version of Self-Care of Coronary Heart Disease Inventory. BACKGROUND: Self-care is a significant step to impede the progression of coronary heart disease and serves as the primary outcome in self-care interventions. In China, however, no instrument is available to measure self-care in patients with coronary heart disease. To address this gap, we introduce the Self-Care of Coronary Heart Disease Inventory into China. DESIGN: A cross-sectional design. METHODS: We translated the inventory into Chinese using standardized methods. Then, it was psychometrically tested on a convenience sample of 301 patients with coronary heart disease (October 2017 to May 2018). Construct validity was evaluated via exploratory factor analysis and testing hypotheses. Internal consistency reliability was measured with Cronbach's alpha or composite reliability. RESULTS: Both self-care maintenance and management subscales showed a two-factor structure, whereas self-care confidence subscale showed a one-dimension structure. All subscales were significantly correlated with associated variables (disease-related knowledge and perceived control). The internal consistency reliability for all three subscales was acceptable. CONCLUSION: The Chinese version showed acceptable psychometric properties when applied to the sample group of this study. It is recommended for use in self-care interventions targeting coronary heart disease.
Subject(s)
Coronary Disease/therapy , Psychometrics/methods , Self Care , Adult , Asian People , China , Cross-Sectional Studies , Factor Analysis, Statistical , Female , Humans , Male , Middle Aged , Reproducibility of Results , Surveys and Questionnaires , TranslatingABSTRACT
In this systematic review and meta-analysis, we evaluated the effectiveness, safety and comfort of StatLock for the securement of peripherally-inserted central catheters. PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, WanFang Database, and China Science and Technology Journal Database were searched. Randomized, controlled trials comparing StatLock with tape or suture on the performance of securing peripherally-inserted central catheters were selected. Meta-analysis was performed using Review Manager 5.3 software. Thirteen randomized, controlled trials involving 1970 patients were included. Our results showed that StatLock reduced the incidence of catheter dislodgement and unplanned removal. Moreover, patients in the StatLock group had lower incidence of skin ulceration, phlebitis, catheter-related bloodstream infection, and cellulitis, and felt more comfortable compared with those in the control group. Current evidence suggests that the StatLock securement device offer advantages over tape and suture in preventing catheter-related complications and improving patient comfort. However, as considerable heterogeneity was found among the included studies, and the quality of evidence for main outcomes was relatively low, the results should be viewed with caution.
Subject(s)
Catheterization, Central Venous/instrumentation , Catheterization, Peripheral/instrumentation , Equipment Design/standards , Equipment Safety/standards , China , Humans , Postoperative Complications/prevention & controlABSTRACT
Background: Acute myocardial infarction (AMI) is a common and serious cardiovascular disease (CVD) that is one of the leading causes of death among women globally and in China. However, there are sex-associated differences and inequalities in the detection and management of AMI, especially in older people. There is little research demonstrating how challenges and barriers affect older women's help-seeking behavior and health-related procedures in China. Purpose: The objective of this study was to explore the experiences of older women with AMI, focusing on their perception, challenges, and coping strategies at the onset of AMI in Wuhan, China. Methods: This study utilized a qualitative research design approach and conducted semi-structured, in-depth, and audio-recorded interviews with 18 women aged 65-84 years, purposively selected from two tertiary hospitals in Wuhan City from November 2021 to April 2022. Results: Interpretative Phenomenological Analysis (IPA) was used in this study to analyze the data on 18 participants and three major themes were generated: disease perception disorder, negative coping strategies, and barriers due to social-environmental contexts. Conclusion: To reduce older women's delay in seeking help, healthcare professionals should provide public health education that emphasizes sex-related disparities, and age-specific knowledge-attitude aspects to high-risk groups. Policy-based and health administration recommendations, including e-health information support, access to care, and social-environmental factors, should be highlighted to promote women's health behavior.
Subject(s)
Delivery of Health Care , East Asian People , Healthcare Disparities , Myocardial Infarction , Aged , Female , Humans , Attitude , Health Behavior , Myocardial Infarction/diagnosis , Myocardial Infarction/therapy , Qualitative Research , Aged, 80 and over , Sex FactorsABSTRACT
OBJECTIVES: To explore the association of the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR) with cancer-related fatigue (CRF) and quality of life (QOL) in cancer patients. DESIGN: A cross-sectional study. SETTINGS: A grade A tertiary hospital in Wuhan, China. PARTICIPANTS: A total of 236 participants were recruited. Participants who were diagnosed with cancer received chemotherapy and/or radiotherapy, and aged ≥18 years were included in this study. PRIMARY AND SECONDARY OUTCOME MEASURES: The PLR, NLR and LMR were calculated based on the absolute lymphocyte count, neutrophil count, platelet count and monocyte count. The CRF and QOL of patients after the first chemotherapy/radiotherapy were evaluated. RESULTS: The median values (IQR) of PLR, NLR and LMR were 174.51 (126.14-261.02), 2.84 (1.64-5.24) and 2.56 (1.30-3.72), respectively. Univariate analysis indicated that high PLR (≥ 174.51), high NLR (≥ 2.84) and low LMR (< 2.56) at baseline significantly correlated with CRF and poor QOL after the first chemotherapy/radiotherapy (p<0.005). Multiple linear regression analysis indicated that elevated PLR might be an independent risk factor for CRF (p<0.001) and QOL (p=0.010) in cancer patients. CONCLUSION: PLR, NLR and LMR are associated with CRF and QOL in cancer patients. High PLR may predict severe CRF and poor QOL. Further studies are needed to validate these findings based on the expanded sample size.
Subject(s)
Fatigue , Monocytes , Neoplasms , Adolescent , Adult , Humans , Cross-Sectional Studies , Lymphocytes , Neoplasms/complications , Neoplasms/psychology , Neutrophils , Quality of Life , Retrospective StudiesABSTRACT
Evidence from histopathology and clinical imaging suggest that choroidal anatomy and hemodynamic perfusion are among the earliest changes in retinal diseases such as age-related macular degeneration (AMD). However, how inner choroidal anatomy affects hemodynamic perfusion is not well understood. Therefore, we sought to understand the influences of choroidal microvascular architecture on the spatial distribution of hemodynamic parameters in choriocapillaris from human donor eyes using image-based computational hemodynamic (ICH) simulations. We subjected image-based inner choroid reconstructions from eight human donor eyes to ICH simulation using a kinetic-based volumetric lattice Boltzmann method to compute hemodynamic distributions of velocity, pressure, and endothelial shear stress. Here, we demonstrate that anatomic parameters, including arteriolar and venular arrangements and intercapillary pillar density and distribution exert profound influences on inner choroidal hemodynamic characteristics. Reductions in capillary, arteriolar, and venular density not only reduce the overall blood velocity within choriocapillaris, but also substantially increase its spatial heterogeneity. These first-ever findings improve understanding of how choroidal anatomy affects hemodynamics and may contribute to pathogenesis of retinal diseases such as AMD.
Subject(s)
Choroid , Macular Degeneration , Humans , Choroid/blood supply , Macular Degeneration/pathology , Hemodynamics , PerfusionABSTRACT
Glioblastoma is the most lethal intracranial malignant tumor, for which the five-year overall survival rate is approximately 5%. Here we explored the therapeutic combination of vitamin C and plasma-conditioned medium on glioblastoma cells in culture and as subcutaneous or intracranial xenografts in mice. The combination treatment reduced cell viability and proliferation while promoting apoptosis, and the effects were significantly stronger than with either treatment on its own. Similar results were obtained in the two xenograft models. Vitamin C appeared to upregulate aquaporin-3 and enhance the uptake of extracellular H2O2, while the combination treatment increased intracellular levels of reactive oxygen species including H2O2 and activated the JNK signaling pathway. The cytotoxic effects of the combination treatment were partially reversed by the specific JNK signaling inhibitor SP600125. Our results suggest that the combination of vitamin C and plasma-conditioned medium has therapeutic potential against glioblastoma, and they provide mechanistic insights that may help investigate this and other potential therapies in greater depth.
Subject(s)
Antineoplastic Agents , Glioblastoma , Humans , Animals , Mice , Glioblastoma/metabolism , Hydrogen Peroxide/metabolism , Culture Media, Conditioned/pharmacology , Ascorbic Acid/pharmacology , Cell Line, Tumor , Apoptosis , Antineoplastic Agents/pharmacology , Reactive Oxygen Species/metabolism , Vitamins/pharmacologyABSTRACT
Background: Enhanced recovery after surgery (ERAS) protocols are well established. Evidence describing nurses' knowledge of ERAS is limited.Aim: To assess surgical nurses' knowledge of ERAS and identify factors that correlate with knowledge level.Design: An anonymous cross-sectional survey via an online social platform was conducted in the abdominal surgical specialty of 40 hospitals in ten cities in China.Methods: Nurses of abdominal surgery in hospitals were enrolled in this study. A self-administered questionnaire that was reviewed by an expert panel was used to assess the knowledge of ERAS in nurses. A generalised linear regression analysis was used to assess factors associated with nurses' knowledge regarding ERAS.Results: Overall survey participation was 91.8% (2230/2430). The mean score of ERAS-related knowledge among abdominal surgical nurses was 12.10 (SD = 3.79). ERAS knowledge differed according to gender, age, education level, professional title, years of working, specialised working years, ERAS training experience, surgical department, and type of hospital (p < 0.05).Conclusions: Chinese nurses employed in abdominal surgical services need to improve the knowledge about ERAS protocols. Standardised training is recommended to improve nurses' ERAS-related knowledge, which can help nurses improve the quality of perioperative care and promote the recovery of patients.
Subject(s)
Enhanced Recovery After Surgery , Nurses , Humans , Cross-Sectional Studies , Clinical Competence , Surveys and QuestionnairesABSTRACT
BACKGROUND AND PURPOSE: Progressive muscle relaxation training (PMRT) has been widely applied to improve the physical and mental health of patients. The aim of this study was to evaluate the effects of PMRT on the symptoms and quality of life (QOL) of cancer patients. METHODS: Nine databases (Web of Science, CENTRAL, PubMed, Embase, CINAHL, OpenGrey, CNKI, Wanfang, and VIP database) were searched to identify randomized controlled trials (RCTs) that assessed the effects of PMRT on health-related outcomes for cancer patients. The risk of bias of the included studies and the evidence quality were appraised using the Cochrane Risk of Bias 2.0 tool and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach, respectively. Meta-analysis was performed using RevMan 5.4. RESULTS: Twelve RCTs sampling 1147 patients were included. PMRT showed significant effects of alleviating anxiety [standardized mean difference (SMD) = -1.32, 95% CI (-1.88, -0.75), P < 0.001] and pain [SMD = -1.02, 95% CI (-1.93, -0.11), P = 0.030], and improving QOL [SMD = 1.65, 95% CI (0.53, 2.76), P = 0.004] in cancer patients. Regarding depression, self-esteem, nausea, and vomiting, PMRT showed better effects compared to the control group. However, no significant effect of reducing fatigue was detected [SMD = -1.00, 95% CI (-2.27, 0.27), P = 0.120]. The overall quality of evidence was moderate to very low. CONCLUSION: PMRT is a promising complementary therapy that may improve the health-related outcomes of cancer patients. Future studies with rigorous research design are needed to obtain valid conclusions.
Subject(s)
Autogenic Training , Neoplasms , Humans , Randomized Controlled Trials as Topic , Anxiety/therapy , Fatigue/therapy , Quality of Life , Neoplasms/therapy , Neoplasms/psychologyABSTRACT
INTRODUCTION: The number of patients with advanced cancer is rapidly increasing, and the disease burden among those with low socioeconomic status (SES) has accordingly become a global concern. Low SES can adversely impact patients with advanced cancer. The purpose of this systematic review is to shed light on the life experiences of patients with advanced cancer with low SES to help provide targeted and effective strategies to improve their quality of life. METHODS AND ANALYSIS: We will include the following English databases: Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, PubMed, MEDLINE, Embase, Web of Science, Joanna Briggs Institute (JBI) Database of Systematic Reviews, PsycINFO and OpenGrey, and the following Chinese databases: China National Knowledge Infrastructure, VIP Database for Chinese Technical Periodicals and Wanfang Data Knowledge Service Platform. A comprehensive search of qualitative studies on the experiences of patients with advanced cancer with low SES will be conducted from the above databases, with no age limit. Quality assessments of the studies will be independently performed by two reviewers using the JBI Critical Assessment Checklist, and any disagreements will be resolved through a discussion with a third reviewer. Relevant data will be extracted using the JBI standardised data extraction tools. The JBI meta-aggregation tool will be used to compare, analyse and summarise the original results. The reliability and credibility of the overall quality of the studies included will be evaluated using the JBI ConQual approach. ETHICS AND DISSEMINATION: This study is based on existing public literature and therefore does not require a formal ethics review. The results of the study may be presented in peer-reviewed international journals and presented at scientific conferences. PROSPERO REGISTRATION NUMBER: CRD42021250423.
Subject(s)
Neoplasms , Quality of Life , Humans , Neoplasms/therapy , Reproducibility of Results , Social Class , Systematic Reviews as TopicABSTRACT
Background: Pseudorabies virus (PRV) is a common pathogen found in pigs. The pathogenicity of PRV in humans is under researched and there are few confirmed cases of PRV infections in humans, which has led to a lack of clinical consensus. Methods: We presented a case of viral encephalitis caused by PRV in China. We performed a systematic review of the literature to investigate the clinical features and prognosis of PRV encephalitis and included 12 patients with PRV encephalitis. Results: All the patients had a history of direct or indirect contact with living pigs or pork before the onset of the disease, accompanied by prodromal symptoms, such as fever and headache. They presented with a series of lesions involving the central nervous system (CNS) and respiratory system, such as acute encephalitis syndrome, respiratory failure, retinitis, or endophthalmitis. Conclusions: The differential diagnosis of an acute attack of CNS infection should include PRV encephalitis, which should be diagnosed by a head magnetic resonance imaging (MRI), fundus examination, and cerebrospinal fluid next-generation sequencing. Intravenous immunoglobulin, glucocorticoid, antiviral, and symptomatic support treatment should be administered as early as possible to improve the prognosis.
Subject(s)
Encephalitis , Herpesvirus 1, Suid , Pseudorabies , Swine Diseases , Animals , China , Encephalitis/veterinary , Herpesvirus 1, Suid/genetics , Humans , Pseudorabies/diagnosis , Pseudorabies/pathology , SwineABSTRACT
Renal arterial stenosis (RAS) often causes renovascular hypertension, which may result in kidney failure and life-threatening consequences. Direct assessment of the hemodynamic severity of RAS has yet to be addressed. In this work, we present a computational concept to derive a new, noninvasive, and patient-specific index to assess the hemodynamic severity of RAS and predict the potential benefit to the patient from a stenting therapy. The hemodynamic index is derived from a functional relation between the translesional pressure indicator (TPI) and lumen volume reduction (S) through a parametric deterioration of the RAS. Our in-house computational platform, InVascular, for image-based computational hemodynamics is used to compute the TPI at given S. InVascular integrates unified computational modeling for both image processing and computational hemodynamics with graphic processing unit parallel computing technology. The TPI-S curve reveals a pair of thresholds of S indicating mild or severe RAS. The TPI at S = 0 represents the pressure improvement following a successful stenting therapy. Six patient cases with a total of 6 aortic and 12 renal arteries are studied. The computed blood pressure waveforms have good agreements with the in vivo measured ones and the systolic pressure is statistical equivalence to the in-vivo measurements with p < .001. Uncertainty quantification provides the reliability of the computed pressure through the corresponding 95% confidence interval. The severity assessments of RAS in four cases are consistent with the medical practice. The preliminary results inspire a more sophisticated investigation for real medical insights of the new index. This computational concept can be applied to other arterial stenoses such as iliac stenosis. Such a noninvasive and patient-specific hemodynamic index has the potential to aid in the clinical decision-making of interventional treatment with reduced medical cost and patient risks.
Subject(s)
Hemodynamics , Kidney , Blood Pressure , Constriction, Pathologic , Humans , Reproducibility of ResultsABSTRACT
Image-based computational fluid dynamics (CFD) has become a new capability for determining wall stresses of pulsatile flows. However, a computational platform that directly connects image information to pulsatile wall stresses is lacking. Prevailing methods rely on manual crafting of a hodgepodge of multidisciplinary software packages, which is usually laborious and error-prone. We present a new computational platform, to compute wall stresses in image-based pulsatile flows using the volumetric lattice Boltzmann method (VLBM). The novelty includes: (1) a unique image processing to extract flow domain and local wall normality, (2) a seamless connection between image extraction and VLBM, (3) an en-route calculation of strain-rate tensor, and (4) GPU acceleration (not included here). We first generalize the streaming operation in the VLBM and then conduct application studies to demonstrate its reliability and applicability. A benchmark study is for laminar and turbulent pulsatile flows in an image-based pipe (Reynolds number: 10 to 5000). The computed pulsatile velocity and shear stress are in good agreements with Womersley's analytical solutions for laminar pulsatile flows and concurrent laboratory measurements for turbulent pulsatile flows. An application study is to quantify the pulsatile hemodynamics in image-based human vertebral and carotid arteries including velocity vector, pressure, and wall-shear stress. The computed velocity vector fields are in reasonably well agreement with MRA (magnetic resonance angiography) measured ones. This computational platform is good for image-based CFD with medical applications and pore-scale porous media flows in various natural and engineering systems.
ABSTRACT
New and efficient drug delivery to the posterior part of the eye is a growing health necessity worldwide. Current treatment of eye diseases, such as age-related macular degeneration (AMD), relies on repeated intravitreal injections of drug-containing solutions. Such a drug delivery has major drawbacks including short drug life, significant medical service, and high medical cost. In this study, we explored a new approach to controlled drug delivery by introducing unique porous implants. Our computational modeling contained key physiological and anatomical traits. Incompressible flow in a porous media field, including the sclera, choroid, and retina layers, is governed by Darcy law and the time evolution of the drug concentration was solved via three convection-diffusion equations in the three layers, respectively. The computational model was validated by established results from independent studies and experimental data. Simulations of the IgG1 Fab drug delivery to the posterior eye were performed to evaluate the effectiveness of the porous implants for controlled delivery. Overall, our results indicate that drug therapeutic levels in the posterior eye sustain for eight weeks similarly to those using intravitreal injection. We first evaluated the effects of the porous implants on the drug delivery in the posterior layers. Subsequent simulations were carried out with varying porosity values in a porous episcleral implant. We found that the time evolution of drug concentration is distinctively correlated to drug source location and pore size. A correlation between porosity and fluid properties for selected porous implants was revealed for the first time in this study.
Subject(s)
Drug Delivery Systems , Sclera , Computer Simulation , Porosity , RetinaABSTRACT
The present study investigated the effects of dexmedetomidine on the expression level of microRNA-320 (miR-320) and neuroglobin (NGB) in patients undergoing off-pump coronary artery bypass grafting (OPCABG). A total of 40 patients undergoing OPCABG were recruited and randomly divided into the dexmedetomidine and normal saline groups (treated before anesthesia), respectively. The NGB levels in the blood samples before and after surgery were analyzed and compared. The CATH.a cells were cultured and induced with dexmedetomidine, and the NGB expression level was detected. CATH.a cells were treated with NGB and lipopolysaccharide (LPS), and the cell survival rate was determined. The miR-320 expression levels in the blood samples and dexmedetomidine-induced cells were detected. Dual-luciferase reporter assay was performed. Compared with control subjects, patients in the dexmedetomidine group had higher NGB levels in the blood. In the CATH.a cells, the dexmedetomidine treatment upregulated the NGB levels. Moreover, upon pre-incubation with NGB and LPS stimulation, dexmedetomidine elevated cell viability. Furthermore, miR-320 expression levels were significantly downregulated in the blood of patients in the dexmedetomidine group, as well as in the dexmedetomidine-induced cells. Dual-luciferase reporter assay confirmed that miRNA-320a directly targeted on NGB, and upregulated miRNA-320a in CATH.a cells decreased cell proliferation activity. Pre-administration of dexmedetomidine can decrease miR-320 expression level in the blood of patients undergoing OPCABG, stimulating the high expression of NGB and increasing the proliferation activity of neuronal cells, which may decrease the postoperative cognitive impairment.
ABSTRACT
Background: Coronavirus disease 2019 (COVID-19) has outbroken in China and subsequently spread worldwide since the end of 2019. Chest computed tomography (CT) plays an important role in the diagnosis of lung diseases, but its value in the diagnosis of cardiac injury remains unknown. Methods: We enrolled 241 consecutive hospitalized patients (aged 61 ± 16 years, 115 males) with laboratory-confirmed COVID-19 at Renmin Hospital of Wuhan University from January 11 to March 2, 2020. They were divided into two groups according to whether major adverse cardiovascular events (MACEs) occurred during the follow-up. The anteroposterior diameter of the left atrium (LAD), the length of the left ventricle (LV), and cardiothoracic ratio (CTR) were measured. The values of myocardial CT were also recorded. Results: Of 241 patients, 115 patients (47.7%) had adverse cardiovascular events. Compared with no MACEs, patients with MACEs were more likely to have bilateral lesions (95.7% vs. 86.5%, p = 0.01). In multivariable analysis, bronchial wall thickening would increase the odds of MACEs by 13.42 (p = 0.01). LAD + LV and CTR was the best predictor for MACEs (area under the curve = 0.88, p < 0.001) with a sensitivity of 82.6% and a specificity of 80.2%. Plasma high-sensitivity troponin I levels in patients with cardiac injury showed a moderate negative correlation with minimum CT value (R 2 = -0.636, p < 0.001). Conclusions: Non-contrast chest CT can be a useful modality for detection cardiac injury and provide additional value to predict MACEs in COVID-19 patients.
ABSTRACT
We study time evolution of velocity and pressure gradients in isotropic turbulence by quantifying their autocorrelation functions and decorrelation time scales. The Lagrangian analysis uses data in a public database generated by direct numerical simulation at a Reynolds number Re{lambda} approximately 433. It is confirmed that when averaging over the entire domain, correlation functions decay on time scales on the order of the global Kolmogorov turnover time scale. However, when performing the analysis in different subregions of the flow, turbulence intermittency leads to large spatial variability in the decay time scales. Remarkably, excellent collapse of the autocorrelation functions is recovered when using a locally defined Kolmogorov time scale. This provides new evidence for the validity of Kolmogorov's refined similarity hypothesis, but from a Lagrangian viewpoint that provides a natural frame to describe the dynamics of turbulence.