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We constructed a photoanode comprising the homogeneous water oxidation catalyst (WOC) Na8K8[Co9(H2O)6(OH)3(HPO4)2(PW9O34)3] (Co9POM) and nanoporous n-type TiO2 photoelectrodes (henceforth "TiO2-Co9POM") by first anchoring the cationic 3-aminopropyltrimethoxysilane (APS) ligand on a metal oxide light absorber, followed by treatment of the metal oxide-APS with a solution of the polyoxometalate WOC. The resulting TiO2-Co9POM photoelectrode exhibits a 3-fold oxygen evolution photocurrent enhancement compared to bare TiO2 in aqueous acidic conditions. Three-element (Co 2p, W 4f, and O 1s) X-ray photoelectron spectroscopy and Raman spectroscopy studies before and after use indicate that surface-bound Co9POM retains its structural integrity throughout all photoelectrochemical water oxidation studies reported here. Extensive charge-transfer mechanistic studies by photoelectrochemical techniques and transient absorption spectroscopy elucidate that Co9POM serves as an efficient WOC, extracting photogenerated holes from TiO2 on the picosecond time scale. This is the first comprehensive mechanistic investigation elucidating the roles of polyoxometalates in POM-photoelectrode hybrid oxygen evolution reaction systems.
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When multiple influential covariates need to be balanced during a clinical trial, stratified blocked randomization and covariate-adaptive randomization procedures are frequently used in trials to prevent bias and enhance the validity of data analysis results. The latter approach is increasingly used in practice for a study with multiple covariates and limited sample sizes. Among a group of these approaches, the covariate-adaptive procedures proposed by Pocock and Simon are straightforward to be utilized in practice. We aim to investigate the optimal design parameters for the patient treatment assignment probability of their developed three methods. In addition, we seek to answer the question related to the randomization performance when additional covariates are added to the existing randomization procedure. We conducted extensive simulation studies to address these practically important questions.
Subject(s)
Research Design , Humans , Computer Simulation , Probability , Random Allocation , Sample Size , Clinical Trials as TopicABSTRACT
A recent report established that the tetrabutylammonium (TBA) salt of hexavanadopolymolybdate TBA4H5[PMo6V6O40] (PV6Mo6) serves as the redox buffer with Cu(II) as a co-catalyst for aerobic deodorization of thiols in acetonitrile. Here, we document the profound impact of vanadium atom number (x = 0-4 and 6) in TBA salts of PVxMo12-xO40(3+x)- (PVMo) on this multicomponent catalytic system. The PVMo cyclic voltammetric peaks from 0 to -2000 mV vs Fc/Fc+ under catalytic conditions (acetonitrile, ambient T) are assigned and clarify that the redox buffering capability of the PVMo/Cu catalytic system derives from the number of steps, the number of electrons transferred each step, and the potential ranges of each step. All PVMo are reduced by varying numbers of electrons, from 1 to 6, in different reaction conditions. Significantly, PVMo with x ≤ 3 not only has much lower activity than when x > 3 (for example, the turnover frequencies (TOF) of PV3Mo9 and PV4Mo8 are 8.9 and 48 s-1, respectively) but also, unlike the latter, cannot maintain steady reduction states when the Mo atoms in these polyoxometalate (POMs) are also reduced. Stopped-flow kinetics measurements reveal that Mo atoms in Keggin PVMo exhibit much slower electron transfer rates than V atoms. There are two kinetic arguments: (a) In acetonitrile, the first formal potential of PMo12 is more positive than that of PVMo11 (-236 and -405 mV vs Fc/Fc+); however, the initial reduction rates are 1.06 × 10-4 s-1 and 0.036 s-1 for PMo12 and PVMo11, respectively. (b) In aqueous sulfate buffer (pH = 2), a two-step kinetics is observed for PVMo11 and PV2Mo10, where the first and second steps are assigned to reduction of the V and Mo centers, respectively. Since fast and reversible electron transfers are key for the redox buffering behavior, the slower electron transfer kinetics of Mo preclude these centers functioning in redox buffering that maintains the solution potential. We conclude that PVMo with more vanadium atoms allows the POM to undergo more and faster redox changes, which enables the POM to function as a redox buffer dictating far higher catalytic activity.
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The control of the solution electrochemical potential as well as pH impacts products in redox reactions, but the former gets far less attention. Redox buffers facilitate the maintenance of potentials and have been noted in diverse cases, but they have not been a component of catalytic systems. We report a catalytic system that contains its own built-in redox buffer. Two highly synergistic components (a) the tetrabutylammonium salt of hexavanadopolymolybdate TBA4H5[PMo6V6O40] (PV6Mo6) and (b) Cu(ClO4)2 in acetonitrile catalyze the aerobic oxidative deodorization of thiols by conversion to the corresponding nonodorous disulfides at 23 °C (each catalyst alone is far less active). For example, the reaction of 2-mercaptoethanol with ambient air gives a turnover number (TON) = 3 × 102 in less than one hour with a turnover frequency (TOF) of 6 × 10-2 s-1 with respect to PV6Mo6. Multiple electrochemical, spectroscopic, and other methods establish that (1) PV6Mo6, a multistep and multielectron redox buffering catalyst, controls the speciation and the ratio of Cu(II)/Cu(I) complexes and thus keeps the solution potential in different narrow ranges by involving multiple POM redox couples and simultaneously functions as an oxidation catalyst that receives electrons from the substrate; (2) Cu catalyzes two processes simultaneously, oxidation of the RSH by PV6Mo6 and reoxidation of reduced PV6Mo6 by O2; and (3) the analogous polytungstate-based system, TBA4H5[PW6V6O40] (PV6W6), has nearly identical cyclic voltammograms (CV) as PV6Mo6 but has almost no catalytic activity: it does not exhibit self-redox buffering.
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In recent years, adaptive randomization methods have gained significant popularity in clinical research and trial design due to their ability to provide both efficiency and flexibility in adjusting the statistical procedures of ongoing clinical trials. For a study to compare multiple treatments, a multi-arm two-stage design could be utilized to select the best treatment from the first stage and further compare that treatment with control in the second stage. The traditional design used equal randomization in both stages. To better utilize the interim results from the first stage, we propose to develop response adaptive randomization two-stage designs for a multi-arm clinical trial with binary outcome. Two allocation methods are considered: (1) an optimal allocation based on a sequential design; (2) the play-the-winner rule. Optimal multi-arm two-stage designs are obtained under three criteria: minimizing the expected number of failures, minimizing the average expected sample size, and minimizing the expected sample size under the null hypothesis. Simulation studies show that the proposed adaptive design based on the play-the-winner rule has good performance. A phase II trial for patients with pancreas adenocarcinoma and a germline BRCA/PALB2 mutation was used to illustrate the application of the proposed response adaptive randomization designs.
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INTRODUCTION: Geriatric assessment (GA) is widely used to detect vulnerability in older patients. As this process is time-consuming, prescreening tools have been developed to identify patients at risk for frailty. We aimed to assess whether the Geriatric 8 (G8) or the Korean Cancer Study Group Geriatric Score (KG-7) shows better performance in identifying patients who are in need of full GA. MATERIALS AND METHODS: A consecutive series of patients aged ≥ 60 years with colorectal cancer were included. The sensitivity, specificity, predictive value, and 95% confidence intervals (95% CI) were calculated for the G8 and the KG-7 using the results of GA as the reference standard. ROC(Receiver Operating Characteristic) was used to evaluate the accuracy of the G8 and the KG-7. RESULTS: One hundred four patients were enrolled. A total of 40.4% of patients were frail according to GA, and 42.3% and 50.0% of patients were frail based on the G8 and the KG-7, respectively. The sensitivity and specificity of the G8 were 90.5% (95% CI: 77.4-97.3%) and 90.3% (95% CI: 80.1-96.4%), respectively. For the KG-7, the sensitivity and specificity were 83.3% (95% CI: 68.6-93.0%) and 72.6% (95% CI: 59.8-83.1%), respectively. Compared to the KG-7, the G8 had a higher predictive accuracy (AUC: (95% CI): 0.90 (0.83-0.95) vs. 0.78 (0.69-0.85); p < 0.01). By applying the G8 and the KG-7, 60 and 52 patients would not need a GA assessment, respectively. CONCLUSION: Both the G8 and the KG-7 showed a great ability to detect frailty in older patients with colorectal cancer. In this population, compared to the KG-7, the G8 had a better performance in identifying those in need of a full Geriatric Assessment.
Subject(s)
Colorectal Neoplasms , Frailty , Neoplasms , Aged , Humans , Frailty/diagnosis , Frail Elderly , Early Detection of Cancer , Neoplasms/diagnosis , Sensitivity and Specificity , Geriatric Assessment/methods , Colorectal Neoplasms/diagnosisABSTRACT
Mixed 3d metal oxides are some of the most promising water oxidation catalysts (WOCs), but it is very difficult to know the locations and percent occupancies of different 3d metals in these heterogeneous catalysts. Without such information, it is hard to quantify catalysis, stability, and other properties of the WOC as a function of the catalyst active site structure. This study combines the site selective synthesis of a homogeneous WOC with two adjacent 3d metals, [Co2Ni2(PW9O34)2]10- (Co2Ni2P2) as a tractable molecular model for CoNi oxide, with the use of multiwavelength synchrotron X-radiation anomalous dispersion scattering (synchrotron XRAS) that quantifies both the location and percent occupancy of Co (â¼97% outer-central-belt positions only) and Ni (â¼97% inner-central-belt positions only) in Co2Ni2P2. This mixed-3d-metal complex catalyzes water oxidation an order of magnitude faster than its isostructural analogue, [Co4(PW9O34)2]10- (Co4P2). Four independent and complementary lines of evidence confirm that Co2Ni2P2 and Co4P2 are the principal WOCs and that Co2+(aq) is not. Density functional theory (DFT) studies revealed that Co4P2 and Co2Ni2P2 have similar frontier orbitals, while stopped-flow kinetic studies and DFT calculations indicate that water oxidation by both complexes follows analogous multistep mechanisms, including likely Co-OOH formation, with the energetics of most steps being lower for Co2Ni2P2 than for Co4P2. Synchrotron XRAS should be generally applicable to active-site-structure-reactivity studies of multi-metal heterogeneous and homogeneous catalysts.
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Although controlling the primary structure of synthetic polymers is itself a great challenge, the potential of sequence control for tailoring hierarchical structures remains to be exploited, especially in the creation of new and unconventional phases. A series of model amphiphilic chain-like giant molecules was designed and synthesized by interconnecting both hydrophobic and hydrophilic molecular nanoparticles in precisely defined sequence and composition to investigate their sequence-dependent phase structures. Not only compositional variation changed the self-assembled supramolecular phases, but also specific sequences induce unconventional phase formation, including Frank-Kasper phases. The formation mechanism was attributed to the conformational change driven by the collective hydrogen bonding and the sequence-mandated topology of the molecules. These results show that sequence control in synthetic polymers can have a dramatic impact on polymer properties and self-assembly.
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Background: Composite scores have been increasingly used in trials for Alzheimer's disease (AD) to detect disease progression, such as the AD Composite Score (ADCOMS) in the lecanemab trial. Objective: To develop a new composite score to improve the prediction of outcome change. Methods: We proposed to develop a new composite score based on the statistical model in the ADCOMS, by removing duplicated sub-scales and adding the model selection in the partial least squares (PLS) regression. Results: The new AD composite Score with variable Selection (ADSS) includes 7 cognitive sub-scales. ADSS can increase the sensitivity to detect disease progression as compared to the existing total scores, which leads to smaller sample sizes using the ADSS in trial designs. Conclusions: ADSS can be utilized in AD trials to improve the success rate of drug development with a high sensitivity to detect disease progression in early stages.
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The STarT MSK tool was developed to enable risk stratification of patients with common musculoskeletal (MSK) pain conditions and help identify individuals who may require more targeted interventions or closer monitoring in primary care settings, however, its validity in U.S.-based outpatient physical therapy settings has not been investigated. The 10-item Keele STarT MSK risk stratification tool was tested for construct (convergent and discriminant) and predictive validity using a multicenter, prospective cohort study design. Participants (n = 141) receiving physical therapy for MSK pain of the back, neck, shoulder, hip, knee, or multisite regions completed intake questionnaires including the Keele STarT MSK tool, Functional Comorbidity Index (FCI), Optimal Screening for Prediction of Referral and Outcome Review-of-Systems and Optimal Screening for Prediction of Referral and Outcome Yellow Flag tools. Pain intensity, pain interference, and health-related quality of life (Medical Outcomes Study 8-item Short-Form Health Survey (SF-8) physical [PCS] and mental [MCS] component summary scores) were measured at 2- and 6-month follow-up. Participants were classified as STarT MSK tool low (44%), medium (39%), and high (17%) risk. Follow-up rates were 70.2% (2 months) and 49.6% (6 months). For convergent validity, fair relationships were observed between the STarT MSK tool and FCI and SF-8 MCS (r = .35-.37) while moderate-to-good relationships (r = .51-.72) were observed for 7 other clinical measures. For discriminant validity, STarT MSK tool risk-dependent relationships were observed for Optimal Screening for Prediction of Referral and Outcome Review-of-Systems, Optimal Screening for Prediction of Referral and Outcome Yellow Flag, pain interference, and SF-8 PCS (low < medium < high; P < .01) and FCI, pain intensity, and SF-8 MCS (low < medium-or-high; P < .01). For predictive validity, intake STarT MSK tool scores explained additional variability in pain intensity (11.2%, 20.0%), pain interference (7.5%, 14.1%), and SF-8 PCS (8.2%, 12.8%) scores at 2 and 6 months, respectively. This study contributes to the existing literature by providing additional evidence of STarT MSK tool cross-sectional construct validity and longitudinal predictive validity. PERSPECTIVE: This study presents STarT MSK risk stratification tool validity findings from a U.S. outpatient physical therapy sample. The STarT MSK tool has the potential to help physical therapists identify individuals presenting with the most common MSK pain conditions who may require more targeted interventions or closer monitoring.
Subject(s)
Musculoskeletal Pain , Physical Therapy Modalities , Adult , Aged , Female , Humans , Male , Middle Aged , Musculoskeletal Pain/diagnosis , Musculoskeletal Pain/therapy , Outpatients , Pain Measurement/standards , Pain Measurement/methods , Physical Therapy Modalities/standards , Prospective Studies , Reproducibility of Results , Risk Assessment , Surveys and Questionnaires/standards , United StatesABSTRACT
Background: The increased risk of metabolic syndrome (MetS) during the menopausal transition might partly attribute to the changes in follicle-stimulating hormone (FSH) and luteinizing hormone (LH). However, few studies were conducted to examine the associations of FSH and LH concentrations with MetS at the full range of reproductive aging, especially in the US population. The aim of this study is to examine the associations of FSH, LH, and LH/FSH ratio with the risk of MetS and severity score in the US women. Methods: Data were derived from the National Health and Nutrition Examination Survey. Women aged from 35 to 60 years were eligible. MetS was defined as having at least 3 of the following: a waist circumference ≥ 88 cm, a triglycerides level ≥ 150 mg/dL, a high density lipoprotein < 50 mg/dL, a systolic blood pressure ≥ 130 mm Hg or a diastolic blood pressure ≥ 85 mm Hg or taking hypertension medications, or a fasting plasma glucose level ≥100 mg/dL or taking diabetes medications. The MetS severity score was calculated according to race/ethnicity- specific equation. Results: There were 3,831 women included in this study. Increases in serum FSH and LH levels per 1 SD were separately linked to a 22.6% (OR: 0.774; 95% CI: 0.646, 0.929; and P= 0.006) and 18.5% (OR: 0.815; 95% CI: 0.690, 0.962; and P= 0.006) lower risk of MetS only in postmenopausal women. Meanwhile, increases in serum FSH and LH levels per 1SD were associated with a decrease of -0.157 (95% CI :-2.967, -2.034) and -0.078 (95% CI: -2.688, -1.806) MetS severity score in perimenopausal women and -0.195 (95% CI: -2.192, -1.023) and -0.098 (95% CI:-1.884, -0.733) in postmenopausal women. However, LH/FSH ratio had no connections with the risk of MetS and MetS severity score across the menopausal transition. Conclusions: Elevated serum FSH and LH levels, but not LH/FSH ratio, were associated with a lower risk of MetS and MetS severity score, especially in postmenopausal women. Therefore, serum FSH and LH levels might be efficient predictors for screening and identifying women at risk of MetS across the menopausal transition.
Subject(s)
Follicle Stimulating Hormone , Metabolic Syndrome , Female , Humans , Adult , Middle Aged , Metabolic Syndrome/epidemiology , Nutrition Surveys , Menopause , Luteinizing Hormone , Follicle Stimulating Hormone, HumanABSTRACT
Background and Objectives: Little is known about the sarcopenia transition process across different stages among Chinese community-dwelling older adults. We aimed to explore dynamic transitions of sarcopenia and its influencing factors in Chinese older adults. Research Design and Methods: Data were derived from the China Health and Retirement Longitudinal Study. A total of 2856 older adults with complete data in the 2011, 2013, and 2015 waves were included in our study. Participants were categorized into 3 states: no sarcopenia, possible sarcopenia, and sarcopenia according to the Asian Working Group for Sarcopenia 2019 (AWGS 2019) criteria. Continuous-time multistate Markov model was performed to estimate the 1-year transition probabilities and the associated factors of sarcopenia transitions. The association strength was expressed as hazard ratio and 95% confidence interval. Results: The progression and reversion rates between no sarcopenia and sarcopenia state were 6.01 and 9.20 per 100 person-years, respectively. The 1-year progression probability to possible sarcopenia was higher compared with the likelihood of moving to the sarcopenia state (0.127 vs 0.034). The reversion probability to no sarcopenia was also higher among those with possible sarcopenia (0.281 vs 0.157). Older age, rural living, worse cognition status, higher chronic disease numbers, and lower nutrition status measured by body mass index accelerated the sarcopenia progression. Cognition status and body mass index level were related to higher chances of reverting. Discussion and Implications: Possible sarcopenia might be a critical time window to promote sarcopenia reversion. Timely interventions aimed at delaying the progression and facilitating sarcopenia recovery should focus on improving cognitive function and nutrition levels.
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The laboratory mouse is an animal model commonly used in cardiovascular research; however, it has technical challenges as a model for myocardial infarction (MI). In this study, a novel noninvasively ventilated and easily operated experimental mouse model of MI was established in Kunming mice based on a left anterior descending (LAD) coronary artery rupture. Overall, 95% of sham mice and 84% of mice with a ruptured LAD survived the surgery. The results of 2,3,5-triphenyl-2H-tetrazolium chloride and hematoxylin-eosin staining showed that obvious infarcts formed after LAD rupture. ST-segment elevation or depression emerging in the electrocardiogram of the novel MI model indicated a myocardial ischemic injury. Reduced cardiac contractility and increased cardiac troponin I and creatine kinase-MB after LAD-rupture implied myocardial necrosis. Furthermore, the serum levels of IL-1ß and IL-6 were significantly upregulated after LAD-rupture. Overall, the LAD-rupture method, utilizing noninvasive ventilation, was a reliable and easily-performed model of MI in mice.
Subject(s)
Myocardial Infarction , Troponin I , Animals , Chlorides , Creatine Kinase , Disease Models, Animal , Eosine Yellowish-(YS) , Hematoxylin , Interleukin-6 , MiceABSTRACT
Many syringe services programs (SSPs) have established trusting, long-term relationships with their clients and are well situated to provide COVID-19 vaccinations. We examined characteristics and practices of SSPs in the United States that reported providing COVID-19 vaccinations to their clients and obstacles to vaccinating people who inject drugs (PWID). We surveyed SSPs in September 2021 to examine COVID-19 vaccination practices through a supplement to the 2020 Dave Purchase Memorial survey. Of 153 SSPs surveyed, 73 (47.7%) responded to the supplement; 24 of 73 (32.9%) reported providing on-site COVID-19 vaccinations. Having provided hepatitis and influenza vaccinations was significantly associated with providing COVID-19 vaccinations (70.8% had provided them vs 28.6% had not; P = .002). Obstacles to providing vaccination included lack of appropriate facilities, lack of funding, lack of trained staff, and vaccine hesitancy among PWID. SSPs are underused as vaccination providers. Many SSPs are well situated to provide COVID-19 vaccinations to PWID, and greater use of SSPs as vaccination providers is needed.
Subject(s)
COVID-19 , HIV Infections , Substance Abuse, Intravenous , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , HIV Infections/prevention & control , Humans , Needle-Exchange Programs , Substance Abuse, Intravenous/complications , Syringes , United States/epidemiology , VaccinationABSTRACT
Background Acute myocardial infarctions are increasingly common among young adults. We investigated sex and racial differences in the evaluation of chest pain (CP) among young adults presenting to the emergency department. Methods and Results Emergency department visits for adults aged 18 to 55 years presenting with CP were identified in the National Hospital Ambulatory Medical Care Survey 2014 to 2018, which uses stratified sampling to produce national estimates. We evaluated associations between sex, race, and CP management before and after multivariable adjustment. We identified 4152 records representing 29 730 145 visits for CP among young adults. Women were less likely than men to be triaged as emergent (19.1% versus 23.3%, respectively, P<0.001), to undergo electrocardiography (74.2% versus 78.8%, respectively, P=0.024), or to be admitted to the hospital or observation unit (12.4% versus 17.9%, respectively, P<0.001), but ordering of cardiac biomarkers was similar. After multivariable adjustment, men were seen more quickly (hazard ratio [HR], 1.15 [95% CI, 1.05-1.26]) and were more likely to be admitted (adjusted odds ratio, 1.40 [95% CI, 1.08-1.81]; P=0.011). People of color waited longer for physician evaluation (HR, 0.82 [95% CI, 0.73-0.93]; P<0.001) than White adults after multivariable adjustment, but there were no racial differences in hospital admission, triage level, electrocardiography, or cardiac biomarker testing. Acute myocardial infarction was diagnosed in 1.4% of adults in the emergency department and 6.5% of admitted adults. Conclusions Women and people of color with CP waited longer to be seen by physicians, independent of clinical features. Women were independently less likely to be admitted when presenting with CP. These differences could impact downstream treatment and outcomes.
Subject(s)
Chest Pain , Myocardial Infarction , Chest Pain/diagnosis , Chest Pain/epidemiology , Chest Pain/etiology , Emergency Service, Hospital , Female , Humans , Male , Myocardial Infarction/diagnosis , Myocardial Infarction/epidemiology , Myocardial Infarction/therapy , Race Factors , Triage/methods , Young AdultABSTRACT
OBJECTIVES: This study describes harm reduction and health services provided by U.S syringe services programs (SSPs) in 2019 and changes in provision of those services in 2020. METHODS: SSPs were invited to participate in the Dave Purchase Memorial survey in August 2020. We collected programmatic data on services provided in 2019 and at the time of the survey in 2020. We conducted descriptive analyses using Chi-square and McNemar's tests. RESULTS: At the time of the survey, > 60% of SSPs reported increased monthly syringe and naloxone distribution and expansion of home-based and mail-based naloxone delivery in Fall 2020 compared to 2019. Approximately three-quarters of SSPs decreased or stopped providing on-site HIV and HCV testing. Nearly half of SSPs offering on-site medications for opioid use disorder (MOUD) in 2019 increased provision of MOUD in 2020. The proportion of SSPs offering on-site mental health care services and primary care services statistically significantly decreased from 2019 to Fall 2020, but telehealth offerings of these services increased. CONCLUSIONS: Many SSPs that offered health services in 2019 and remained operational in 2020 increased telehealth provision of mental health and primary care services, increased MOUD provision, and expanded harm reduction services, but most SSPs reduced or stopped on-site HIV and HCV testing. Sustaining SSP growth and innovation is paramount for preventing overdose deaths and HIV/HCV outbreaks after the deadliest year of the opioid epidemic in 2020.
Subject(s)
COVID-19 , Substance Abuse, Intravenous , COVID-19/prevention & control , Harm Reduction , Health Services , Humans , Needle-Exchange Programs , SARS-CoV-2 , Substance Abuse, Intravenous/complications , Substance Abuse, Intravenous/epidemiology , SyringesABSTRACT
Resveratrol (RES) is a natural phenol which possesses multiple pharmacological actions. The present study aimed to determine whether RES protects against myocardial ischemic injury in association with the inhibition of NFκBdependent inflammation and the enhancement of antioxidant defenses in mice following acute myocardial infarction (AMI). Male C57/BL mice were randomly assigned to 3 groups as follows: The shamoperated (sham) group, AMI + vehicle group and AMI + RES group. Rat H9C2 cells were also used to examine the effects of RES on hypoxiainduced oxidative injury in vitro. Redox homeostasis in the mouse myocardium and rat H9C2 cells was determined posttreatment. The mRNA and protein levels of phosphorylated (p)IκB kinase (pIKK), pnuclear factor (NF)κB p65, interleukin (IL)1ß, IL6, nerve growth factor (NGF) and insulinlike growth factor1 (IGF1) were measured by RTqPCR and western blot analysis. It was found that RES slightly protected the myocardium against ischemic injury in mice, while it prevented the hypoxiainduced apoptosis of H9C2 cells. RES decreased the production of reactive oxygen species (ROS) and enhanced the activities of superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GPx). RES also downregulated the protein and/or mRNA levels of pIKK, pNFκB p65, IL1ß, IL6, NGF and IGF1 at 7 and 28 days after infarction. On the whole, these data indicate that RES protects the myocardium against ischemic injury in association with the inhibition of oxidative stress and inflammatory responses. Thus, RES has the potential to be used as an adjunctive therapeutic drug for heart diseases.
Subject(s)
Antioxidants/metabolism , Myocardial Reperfusion Injury/metabolism , NF-kappa B/metabolism , Resveratrol/pharmacology , Animals , Cell Line , Inflammation/drug therapy , Inflammation/metabolism , Inflammation/pathology , Male , Mice , Myocardial Reperfusion Injury/drug therapy , Myocardial Reperfusion Injury/pathology , RatsABSTRACT
We have successfully synthesized a series of monodispersed chain-like giant molecules with precisely controlled macromolecular composition and sequence based on polyhedral oligomeric silsesquioxane (POSS) nanoparticles using an orthogonal "click" strategy. Their nonspherical supramolecular structures, such as lamellae, double gyroids, and hexagonal packed cylinders, are mainly determined by the composition (namely, the number of incorporated amphiphilic nanoparticles). In addition, by precisely alternating the sequence of arranged nanoparticles in the giant molecules with identical chemical compositions, the domain sizes of their supramolecular structures could be fine-tuned. This is attributed to the macromolecular conformational differences caused by collective hydrogen bonding interactions in each set of sequence isomeric giant molecules. This work has demonstrated multilevel manipulation of supramolecular structures of giant molecules: coarse tuning by composition and fine-tuning by sequence.
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A series of multi-headed giant surfactants based on polystyrene (PS)-polyhedral oligomeric silsesquioxane(s) (POSS) conjugates, with a different number and topology of POSS heads, are found to self-assemble into different supramolecular structures including vesicles, cylindrical and spherical micelles in H2O/DMF mixed solvents. The transitions among different morphologies can be rationally controlled by tuning the number and topology of POSS heads, as well as the macromolecular concentration.
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OBJECTIVES: Recent evidence indicates that suppressing inflammation by specific drug target and treatment measures contributes to attenuate ischaemic injury and the related heart diseases. This study aimed to investigate the potential effect of baicalin on myocardial ischaemic injury through inhibition of inflammation by inactivating the aryl hydrocarbon receptor (AhR). METHODS: The mouse model with myocardial ischaemic injury was prepared by the left anterior descending coronary artery-amputation and then treated using baicalin. After observing the expression of AhR by immunohistochemical staining, the AhR and inflammatory mediators in circulation and myocardial tissues, including high-sensitive C-reactive protein (hsCRP), interleukin (IL)-1ß and IL-6, were detected based on enzyme-linked immunosorbent assay, real-time polymerase chain reaction and Western blot methods. KEY FINDINGS: The results showed that (1) substantial expression of AhR was observed in myocardial tissues; (2) ischaemic injury caused myocardial necrosis and remodelling, and stimulated hsCRP, IL-1ß and IL-6 by activation of AhR; and (3) baicalin alleviated the myocardial injury and inflammatory response by inhibiting the expression of AhR. CONCLUSION: Our findings extend the list of AhR ligands beyond exogenous toxins and endogenous molecules to cardiac immunological factors, and moreover it could be considered potential drug targets due to its pathological modulatory properties, while baicalin demonstrated promise as a novel vehicle for ischaemic heart disease.