Publications by authors named "Rui Song"

356 Publications

Effects of virtual reality cognitive training in individuals with mild cognitive impairment: A systematic review and meta-analysis.

Int J Geriatr Psychiatry 2021 Jul 27. Epub 2021 Jul 27.

Associate Professor. School of Nursing, Sun Yat-sen University, Guangzhou, China, 510080.

Background: Virtual reality (VR) is used to improve specific health needs by combining multiple technologies, it is increasingly being used in the medical field, showing satisfactory effects, especially in the management of chronic disease. The aim of this study was to assess the effects of VR cognitive training for individuals with mild cognitive impairment (MCI).

Methods: Peer reviewed articles were searched from the PubMed, Embase, Web of Science, the Cochrane Library, Science Direct, and EBSCOhost databases, as well as CNKI, Sinomed, Vip and Wan Fang, through May 23, 2021. We only included randomized controlled trials (RCTs) enrolling participants with MCI.

Results: Seventeen RCTs were included, with a total of 744 participants. Evidence of moderate quality showed that VR cognitive training significantly enhanced MCI patients' global cognitive function, as measured by the Montreal Cognitive Assessment (SMD = 0.42; 95% CI, 0.04 to 0.79; P = 0.03) and executive function, as measured by trail making test A (SMD = -0.58; 95% CI, -0.80 to -0.35; P < 0.001). The meta-analysis indicated that the effects of VR cognitive training on delayed memory, immediate memory, attention and instrumental activities of daily living were not statistically significant (P > 0.05).

Conclusion: The available data showed that VR cognitive training might be beneficial for improving global cognitive function and executive function in individuals with MCI, although the effects were short term. This article is protected by copyright. All rights reserved.
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http://dx.doi.org/10.1002/gps.5603DOI Listing
July 2021

Genome-Wide Identification of GRAS Gene Family and Their Responses to Abiotic Stress in .

Int J Mol Sci 2021 Jul 20;22(14). Epub 2021 Jul 20.

College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China.

Alfalfa () is a high-quality legume forage crop worldwide, and alfalfa production is often threatened by abiotic environmental stresses. GRAS proteins are important transcription factors that play a vital role in plant development, as well as in response to environmental stress. In this study, the availability of alfalfa genome "Zhongmu No.1" allowed us to identify 51 GRAS family members, i.e., MsGRAS. MsGRAS proteins could be classified into nine subgroups with distinct conserved domains, and tandem and segmental duplications were observed as an expansion strategy of this gene family. In RNA-Seq analysis, 14 MsGRAS genes were not expressed in the leaf or root, 6 GRAS genes in 3 differentially expressed gene clusters were involved in the salinity stress response in the leaf. Moreover, qRT-PCR results confirmed that MsGRAS51 expression was induced under drought stress and hormone treatments (ABA, GA and IAA) but down-regulated in salinity stress. Collectively, our genome-wide characterization, evolutionary, and expression analysis suggested that the MsGRAS proteins might play crucial roles in response to abiotic stresses and hormonal cues in alfalfa. For the breeding of alfalfa, it provided important information on stress resistance and functional studies on MsGRAS and hormone signaling.
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http://dx.doi.org/10.3390/ijms22147729DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8304046PMC
July 2021

Adherence to the World Cancer Research Fund/American Institute for Cancer Research cancer prevention recommendations and colorectal cancer survival.

Cancer Epidemiol Biomarkers Prev 2021 Jul 16. Epub 2021 Jul 16.

Department of Nutrition, Harvard T.H. Chan School of Public Health

Background: Cancer patients are recommended to follow cancer prevention guidelines due to inadequate evidence for specific recommendations for cancer survivors.

Methods: We examined whether diet and lifestyle scores measuring adherence to the 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) cancer prevention guidelines were associated with colorectal cancer-specific and overall mortality among 1,491 colorectal cancer (CRC) patients in two prospective cohorts. Cox proportional hazards regression models were used to calculate the multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).

Results: During a median follow-up of 7.92 years, there were 641 deaths (179 CRC-specific deaths). Patients in the highest quartile of the post-diagnostic lifestyle score including diet, body mass index (BMI), and physical activity had a 24% lower risk (HR=0.76, 95% CI: 0.49-1.18) of CRC-specific death and a 37% lower risk (HR=0.63, 95% CI: 0.50-0.78) of overall death compared with the lowest quartile. When BMI was not included in the lifestyle score due to potential disease-related weight loss, stronger inverse associations were observed for both CRC-specific and overall mortality for the same comparison (CRC-specific: HR=0.50, 95% CI: 0.32-0.79; overall: HR=0.59, 95% CI: 0.47-0.75). The post-diagnostic diet score was not statistically significantly associated with either CRC-specific or overall mortality.

Conclusions: Greater adherence to the WCRF/AICR cancer prevention recommendations was associated with improved survival in CRC patients.

Impact: The study provided support for CRC patients to follow cancer prevention recommendations after diagnosis. Future studies on cancer survivors will continue to contribute to evidence-based diet and lifestyle recommendations for cancer patients.
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http://dx.doi.org/10.1158/1055-9965.EPI-21-0120DOI Listing
July 2021

On estimating optimal regime for treatment initiation time based on restricted mean residual lifetime.

Biometrics 2021 Jul 15. Epub 2021 Jul 15.

Department of Statistics, North Carolina State University, Raleigh, NC 27695, USA.

When to initiate treatment on patients is an important problem in many medical studies such as AIDS and cancer. In this article, we formulate the treatment initiation time problem for time-to-event data and propose an optimal individualized regime that determines the best treatment initiation time for individual patients based on their characteristics. Different from existing optimal treatment regimes where treatments are undertaken at a pre-specified time, here new challenges arise from the complicated missing mechanisms in treatment initiation time data and the continuous treatment rule in terms of initiation time. To tackle these challenges, we propose to use restricted mean residual lifetime as a value function to evaluate the performance of different treatment initiation regimes, and develop a nonparametric estimator for the value function, which is consistent even when treatment initiation times are not completely observable and their distribution is unknown. We also establish the asymptotic properties of the resulting estimator in the decision rule and its associated value function estimator. In particular, the asymptotic distribution of the estimated value function is nonstandard, which follows a weighted chi-squared distribution. The finite-sample performance of the proposed method is evaluated by simulation studies and is further illustrated with an application to a breast cancer data. This article is protected by copyright. All rights reserved.
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http://dx.doi.org/10.1111/biom.13530DOI Listing
July 2021

Construction of New Active Sites: Cu Substitution Enabled Surface Frustrated Lewis Pairs over Calcium Hydroxyapatite for CO Hydrogenation.

Adv Sci (Weinh) 2021 Jul 8:e2101382. Epub 2021 Jul 8.

Solar Fuels Group, Centre for Inorganic and Polymeric Nanomaterials, Department of Chemistry, University of Toronto, Toronto, M5S 3H6, Canada.

Calcium hydroxyphosphate, Ca (PO ) (OH) , is commonly known as hydroxyapatite (HAP). The acidic calcium and basic phosphate/hydroxide sites in HAP can be modified via isomorphous substitution of calcium and/or hydroxide ions to enable a cornucopia of catalyzed reactions. Herein, isomorphic substitution of Ca ions by Cu ions especially at very low levels of exchange created new analogs of molecular surface frustrated Lewis pairs (SFLPs) in Cu Ca (PO ) (OH) , thereby boosting its performance metrics in heterogeneous CO photocatalytic hydrogenation. In situ Fourier transform infrared spectroscopy characterization and density functional theory calculations provided fundamental insights into the catalytically active SFLPs defined as proximal Lewis acidic Cu and Lewis basic OH . The photocatalytic pathway proceeds through a formate reaction intermediate, which is generated by the reaction of CO with heterolytically dissociated H on the SFLPs. Given the wealth of information thus uncovered, it is highly likely that this work will spur the further development of similar classes of materials, leading to the advancement and, ultimately, large-scale application of photocatalytic CO reduction technologies.
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http://dx.doi.org/10.1002/advs.202101382DOI Listing
July 2021

Recurrent seizure-related GRIN1 variant: Molecular mechanism and targeted therapy.

Ann Clin Transl Neurol 2021 Jul 6;8(7):1480-1494. Epub 2021 Jul 6.

Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, Georgia, USA.

Objective: Genetic variants in the GRIN genes that encode N-methyl-D-aspartate receptor (NMDAR) subunits have been identified in various neurodevelopmental disorders, including epilepsy. We identified a GRIN1 variant from an individual with early-onset epileptic encephalopathy, evaluated functional changes to NMDAR properties caused by the variant, and screened FDA-approved therapeutic compounds as potential treatments for the patient.

Methods: Whole exome sequencing identified a missense variant in GRIN1. Electrophysiological recordings were made from Xenopus oocytes and transfected HEK cells to determine the NMDAR biophysical properties as well as the sensitivity to agonists and FDA-approved drugs that inhibit NMDARs. A beta-lactamase reporter assay in transfected HEK cells evaluated the effects of the variant on the NMDAR surface expression.

Results: A recurrent de novo missense variant in GRIN1 (c.1923G>A, p.Met641Ile), which encodes the GluN1 subunit, was identified in a pediatric patient with drug-resistant seizures and early-onset epileptic encephalopathy. In vitro analysis indicates that GluN1-M641I containing NMDARs showed enhanced agonist potency and reduced Mg block, which may be associated with the patient's phenotype. Results from screening FDA-approved drugs suggested that GluN1-M641I containing NMDARs are more sensitive to the NMDAR channel blockers memantine, ketamine, and dextromethorphan compared to the wild-type receptors. The addition of memantine to the seizure treatment regimen significantly reduced the patient's seizure burden.

Interpretation: Our finding contributes to the understanding of the phenotype-genotype correlations of patients with GRIN1 gene variants, provides a molecular mechanism underlying the actions of this variant, and explores therapeutic strategies for treating GRIN1-related neurological conditions.
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http://dx.doi.org/10.1002/acn3.51406DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8283169PMC
July 2021

High-efficiency ultra-compact near-infrared supercontinuum generated in an ultrashort cavity configuration.

Opt Express 2021 Jun;29(12):19140-19146

We report a novel method to generate near-infrared supercontinuum (SC) in an ultrashort cavity configuration with only 11.5 m. With the continuous laser diode pump, a near-infrared SC with 26.8 W average output power and a spectrum ranging from 900 nm to 2000nm is demonstrated, and the laser diode pump to supercontinuum conversion efficiency is up to 60%. The spectral and power characteristics of the generated SC under different lengths of germanium-doped fiber (GDF) were carefully studied. This near-infrared SC generation method has the advantages of simple structure, low cost and good stability and also possesses the shortest fiber laser cavity length ever reported to the best of our knowledge.
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http://dx.doi.org/10.1364/OE.425948DOI Listing
June 2021

Saikosaponins and the deglycosylated metabolites exert liver meridian guiding effect through PXR/CYP3A4 inhibition.

J Ethnopharmacol 2021 Jun 18;279:114344. Epub 2021 Jun 18.

Key Laboratory of Drug Quality Control & Pharmacovigilance (China Pharmaceutical University), Ministry of Educational, Nanjing, 210009, China; State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing, 210009, China. Electronic address:

Ethnopharmacological Relevance: Radix Bupleuri (RB), traditionally used to treat inflammatory disorders and infectious diseases, represents one of the most successful and widely used herbal drugs in Asia over the past 2000 years. Being realized the role in regulating metabolism and controlling Yin/Yang, RB is not only chosen specifically for treating liver meridian and the corresponding organs, but also believed to have liver meridian guiding property and help potentiate the therapeutic effects of liver. However, the ingredients in RB with liver meridian guiding property and the underly mechanism have not been comprehensively investigated.

Aim Of Study: Considering the important role of CYP3A4 in first-pass metabolism and the liver exposure of drugs, the present study aimed to determine whether saikosaponins (SSs) and the corresponding saikogenins (SGs) have a role in inhibiting the catalytic activity of CYP3A4 in human liver microsomes and HepG2 hepatoma cells and whether they could suppress CYP3A4 expression by PXR-mediated pathways in HepG2 hepatoma cells.

Materials And Methods: The effect of SSs and SGs on CYP3A4-mediated midazolam1'-hydroxylation activities in pooled human liver microsomes (HLMs) was first studied. Dose-dependent experiments were performed to obtain the half inhibit concentration (IC) values. HepG2 cells were used to assay catalytic activity of CYP3A4, reporter function, mRNA levels, and protein expression. The inhibitory effects of SSa and SSd on CYP3A4 activity are negligible, while the corresponding SGs (SGF and SGG) have obvious inhibitory effects on CYP3A4 activity, with IC values of 0.45 and 1.30 μM. The similar results were obtained from testing CYP3A4 catalytic activity in HepG2 cells, which correlated well with the suppression of the mRNA and protein levels of CYP3A4. Time-dependent testing of CYP3A4 mRNA and protein levels, as well as co-transfection experiments using the CYP3A4 promoter luciferase plasmid, further confirmed that SSs and SGs could inhibit the expression of CYP3A4 at the transcription level. Furthermore, PXR protein expression decreased in a concentration- and time-dependent manner after cells were exposed to SSs and SGs. PXR overexpression and RNA interference experiments further showed that SSs and SGs down-regulate the catalytic activity and expression of CYP3A4 in HepG2 may be mainly through PXR-dependent manner.

Conclusion: SSs and SGs inhibit the catalytic activity and expression of CYP3A4 in a PXR-dependent manner, which may be highly related to the liver meridian guiding property of RB.
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http://dx.doi.org/10.1016/j.jep.2021.114344DOI Listing
June 2021

Combined exome sequencing and deep phenotyping in highly selected fetuses with skeletal dysplasia during the first and second trimesters improves diagnostic yield.

Prenat Diagn 2021 Jun 6. Epub 2021 Jun 6.

Department of Obstetrics and Gynecology, 1st Medical Center of Chinese PLA General Hospital, Beijing, China.

Objective: To investigate the genetic etiology of skeletal dysplasia in highly selected fetuses during the first and second trimesters using deep phenotyping and exome sequencing (ES).

Method: Fetuses with short femurs were identified using the established prenatal diagnostic approach. A multidisciplinary team reviewed fetal phenotypic information (prenatal ultrasound findings, fetal postmortem, and radiographs) in a cohort of highly selected fetuses with skeletal dysplasia during the first and second trimesters. The affected families underwent multiplatform genetic tests.

Results: Of the 27 affected fetuses, 21 (77.8%) had pathogenic or potential pathogenic variations in the following genes: COL1A1, FGFR3, COL2A1, COL1A2, FLNB, DYNC2LI1, and TRIP11. Two fetuses had compound heterozygous mutations in DYNC2LI1 and TRIP11, respectively, and the other 19 carried de novo autosomal dominant variants. Novel variants were identified in COL1A1, COL2A1, COL1A2, DYNC2LI1, and TRIP11 in 11 fetuses. We also included the first description of the phenotype of odontochondrodysplasia in a prenatal setting.

Conclusions: ES or panel sequencing offers a high diagnostic yield for fetal skeletal dysplasia during the first and second trimesters. Comprehensive and complete phenotypic information is indispensable for genetic analysis and the expansion of genotype-phenotype correlations in fetal skeletal abnormalities.
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http://dx.doi.org/10.1002/pd.5974DOI Listing
June 2021

Distinct durability of IgM/IgG antibody responses in COVID-19 patients with differing severity.

Sci China Life Sci 2021 Jun 2. Epub 2021 Jun 2.

CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Center for Influenza Research and Early-warning (CASCIRE), CAS-TWAS Center of Excellence for Emerging Infectious Diseases (CEEID), Chinese Academy of Sciences, Beijing, 100101, China.

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http://dx.doi.org/10.1007/s11427-020-1947-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8176871PMC
June 2021

Integrated multiplatform-based metabonomics and network analysis to explore the mechanism of Polygonum cuspidatum on hyperlipidemia.

J Chromatogr B Analyt Technol Biomed Life Sci 2021 Jun 18;1176:122769. Epub 2021 May 18.

Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210000, China. Electronic address:

Hyperlipidemia is a major risk factor and pathological basis for cardiovascular diseases. Polygonum cuspidatum (HZ), a famous traditional Chinese medicine, is frequently used to treat hyperlipidemia. However, little is known about its underlying mechanism. Herein, an integrated approach combining multiplatform-based metabonomics and network analysis was adopted to elucidate the ameliorative mechanism of HZ on hyperlipidemia. The global metabolomic characters of HZ on hyperlipidemia were investigated by GC-MS and LC-MS based metabonomics. Significant metabonomic alterations were observed in hyperlipidemic group, which could be restored by HZ supplementation. Furthermore, the drug-ingredients-target-metabolic pathway network was constructed, and the result indicated that HZ exhibited hypolipidemic efficacy through resveratrol, polydatin, torachrysone-8-O-β-D-(6'-oxayl)-glucoside, physciondiglucoside, (+)-catechin, β-sitosterol, quercetin, luteolin and physovenine acting on phospholipase A2, unspecific monooxygenase, arachidonate 15-lipoxygenase, aromatic-L-amino-acid decarboxylase, alcohol dehydrogenase and triacylglycerol lipase. In conclusion, this study explored potential mechanism of HZ on hyperlipidemia with the aid of the integrated approach combining multiplatform-based metabonomics and network analysis, which might provide a theoretical basis for the clinical application of HZ.
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http://dx.doi.org/10.1016/j.jchromb.2021.122769DOI Listing
June 2021

Astragaloside IV prevents acute myocardial infarction by inhibiting the TLR4/MyD88/NF-κB signaling pathway.

J Food Biochem 2021 07 25;45(7):e13757. Epub 2021 May 25.

School of Integrated Chinese and Western Medicine, Anhui University of Chinese Medicine, Hefei, P.R. China.

Although astragaloside IV protects from acute myocardial infarction (AMI)-induced chronic heart failure (CHF), the underlying mechanism of action is unclear. We determined the potential therapeutic effect of astragaloside IV using molecular docking approaches and validated the findings by the ligation of the left anterior descending (LAD) coronary artery-induced AMI rat model. The interaction between astragaloside IV and myeloid differentiation factor 88 (MyD88) was evaluated by SwissDock. To explore the mechanisms underlying the beneficial effects of astragaloside IV in the LAD coronary artery ligation-induced AMI model, we administered the rats with astragaloside IV for 4 weeks. Hemodynamic indexes were used to evaluate the degree of myocardial injury in model rats. The histopathological changes in myocardium were detected by hematoxylin & eosin (H&E) staining and Masson's staining. Myocardium homogenate contents of collagen I and collagen III were evaluated by ELISA. The level of myocardial hydroxyproline (HYP) was determined by alkaline hydrolysis. Immunohistochemistry was used to examine collagen I. Western blotting was used to examine relevant proteins. As per the molecular docking study results, astragaloside IV may act on MyD88. Furthermore, astragaloside IV improved hemodynamic disorders, alleviated pathological changes, and reduced abnormal collagen deposition and myocardial HYP in vivo. Astragaloside IV significantly reduced the overexpression of TLR4, MyD88, NF-Κb, and TGF-β, which further validated the molecular docking findings. Hence, astragaloside IV ameliorates AMI by reducing inflammation and blocking TLR4/MyD88/NF-κB signaling. These results indicate that astragaloside IV may alleviate AMI. PRACTICAL APPLICATIONS: Astragaloside IV, a small active substance extracted from Astragalus membranaceus, has demonstrated potent protective effects against cardiovascular ischemia/reperfusion, diabetic nephropathy, and other diseases. Molecular docking experiments showed that astragaloside IV might act on the myeloid differentiation factor 88 (MyD88). Astragaloside IV can effectively reduce the overexpression of TLR4, MyD88, and NF-κB p65, indicating that astragaloside IV inhibits inflammation via TLR4/MyD88/NF-κB signaling pathway. These results indicate that astragaloside IV may alleviate acute myocardial infarction.
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http://dx.doi.org/10.1111/jfbc.13757DOI Listing
July 2021

Early and consecutive RT-PCR tests with both oropharyngeal swabs and sputum could improve testing yield for patients with COVID-19: An observation cohort study in China.

Int J Infect Dis 2021 Jun 28;107:242-246. Epub 2021 Apr 28.

Beijing Ditan Hospital, Capital Medical University, Beijing 100102, China; Beijing Key Laboratory of Emerging Infectious Diseases, Beijing 100102, China. Electronic address:

Objective: The real-time polymerase chain reaction (RT-PCR) test is recommended for the diagnosis of COVID-19 and provides a powerful tool to identify new infections and facilitate contact tracing. In fact, as the prevalence of COVID-19 decreases, this RT-PCR testing remains as the main preventive measure to avoid rebound. However, inconsistent results can lead to misdiagnoses in the clinic. These inconsistencies are due to the variability in (1) the collection times of biological samples post infection, and (2) sampling procedures.

Methods: We applied the Kaplan-Meier method and multivariate logistic regression on RT-PCR results from 258 confirmed patients with COVID-19 to evaluate the factors associated with negative conversion. We also estimated the proportion (%) of negative conversion among patients who had tested twice or more, and compared the proportions arising from oropharyngeal swabs, sputum, and combined double testing, respectively.

Main Results: The proportion of negative conversion was 6.7% on day 4, 16.4% on day 7, 41.0% at 2 weeks, and 61.0% at 3 weeks post-admission. We also found that 34.1% and 60.3% of subjects had at least one negative RT-PCR result on days 7 and 14 after the onset of symptoms, respectively. The proportion of negative conversions following sputum testing was higher than that from oropharyngeal swabs in the early stages but this declined after the onset of symptoms.

Conclusion: In the absence of effective treatments or vaccines, efficient testing strategies are critical if we are to control the COVID-19 epidemic. According to this study, early, consecutive and combined double testing, will be the key to identify infected patients, particularly for asymptomatic and mild symptomatic cases. These strategies will minimize misdiagnosis and the ineffective isolation of infected patients.
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http://dx.doi.org/10.1016/j.ijid.2021.04.076DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8079261PMC
June 2021

Prevalence of psychiatric diagnosis and related psychopathological symptoms among patients with COVID-19 during the second wave of the pandemic.

Global Health 2021 04 8;17(1):44. Epub 2021 Apr 8.

Department of General Medicine, Beijing Ditan Hospital, Capital Medical University, No. 8 Jingshun East Street, Chaoyang District, Beijing, 100015, China.

Background: The possibility of psychopathological symptoms and related risk factors among normal persons and patients infected during the outbreak of COVID-19 has been widely investigated. The mental health outcomes of the second wave of the pandemic remain unclear, especially those of patients with an infection. Thus, this study aims to explore the prevalence of and related risk factors associated with psychopathological symptoms among patients infected with COVID-19 during the second wave.

Method: A cross-sectional survey was conducted in five isolated wards of a designated hospital in Beijing, China, from July 1 to July 15, 2020. The Mini International Neuropsychiatric Interview (MINI) was conducted to assess psychiatric disorders, and a series of scales were used to measure self-reported psychopathological symptoms and psychosomatic factors. Multivariate regression analysis was used to analyze the risk factors associated with psychopathological symptoms.

Results: Among 119 participants with infections, the prevalence of generalized anxiety symptoms (51.3%), depressive symptoms (41.2%), and posttraumatic stress symptoms (PTSS)/posttraumatic stress disorder (PTSD) symptoms (33.6%) was observed. Loneliness, hope, coping strategies, and history of mental disorders were the shared risk or protective factors across several psychopathological symptoms. The perceived impact of COVID-19 is the specific risk factor associated with state anxiety symptoms.

Conclusions: The prevalence of symptoms of depression, anxiety, and PTSS/PTSD is high among patients with infections during the second wave of the pandemic in Beijing. Clinical doctors must realize that these patients will probably experience depressive disorder, anxiety disorders, and PTSS/PTSD, as well as some neuropsychiatric syndromes. Specific mental health care is urgently required to help patients manage the virus during the second wave of the pandemic.
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http://dx.doi.org/10.1186/s12992-021-00694-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8027973PMC
April 2021

Phylogenomic tracing of asymptomatic transmission in a COVID-19 outbreak.

Innovation (N Y) 2021 May 22;2(2):100099. Epub 2021 Mar 22.

Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China.

SARS-CoV-2 has caused over 100 million deaths and continues to spread rapidly around the world. Asymptomatic transmission of SARS-CoV-2 is the Achilles' heel of COVID-19 public health control measures. Phylogenomic data on SARS-CoV-2 could provide more direct information about asymptomatic transmission. In this study, using a novel MINERVA sequencing technology, we traced asymptomatic transmission of COVID-19 patients in Beijing, China. One hundred and seventy-eight close contacts were quarantined, and 14 COVID-19 patients were laboratory confirmed by RT-PCR. We provide direct phylogenomic evidence of asymptomatic transmission by constructing the median joining network in the cluster. These data could help us to determine whether the current symptom-based screening should cover asymptomatic persons.
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http://dx.doi.org/10.1016/j.xinn.2021.100099DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7982642PMC
May 2021

Association of folate intake and colorectal cancer risk in the postfortification era in US women.

Am J Clin Nutr 2021 Jul;114(1):49-58

Department of Nutrition, Harvard TH Chan School of Public Health, Boston, MA, USA.

Background: Folate may play a preventive role in the early stages of colorectal carcinogenesis, but long latencies may be needed to observe a reduction in colorectal cancer (CRC) incidence. In addition, concerns have been raised about the potential for cancer promotion with excessive folate intake, especially after the mandatory folic acid fortification in the United States in 1998.

Objective: We aimed to examine the association between folate intake in different chemical forms and CRC risk, especially in the postfortification era in the United States.

Design: We prospectively followed 86,320 women from the Nurses' Health Study (1980-2016). Folate intake was collected by validated food frequency questionnaires. CRC was self reported and confirmed by review of medical records. The association between the folate intake and CRC risk was assessed using Cox proportional hazards regression.

Results: We documented 1988 incident CRC cases during follow-up. Analyzing folate intake as a continuous variable, greater total folate intake 12-24 y before diagnosis was associated with lower risk of CRC (per increment of 400 dietary folate equivalents (DFE)/d, HR: 0.93, 95% CI: 0.85, 1.01 for 12-16 y; HR: 0.83, 95% CI: 0.75, 0.92 for 16-20 y; and HR: 0.87, 95% CI: 0.77, 0.99 for 20-24 y); and greater synthetic folic acid intake 16-24 y before diagnosis was also associated with a lower CRC risk (per increment of 400 DFE/d, HR: 0.91, 95% CI: 0.84, 0.99 for 16-20 y and HR: 0.91, 95% CI: 0.83-1.01 for 20-24 y). In the postfortification period (1998-2016), intake of total or specific forms of folate was not associated with CRC risk, even among multivitamin users.

Conclusions: Folate intake, both total and from synthetic forms, was associated with a lower risk of overall CRC after long latency periods. There was no evidence that high folate intake in the postfortification period was related to increased CRC risk in this US female population.
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http://dx.doi.org/10.1093/ajcn/nqab035DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8246607PMC
July 2021

Statistical Inference for Online Decision-Making: In a Contextual Bandit Setting.

J Am Stat Assoc 2021 7;116(533):240-255. Epub 2020 Jul 7.

Department of Statistics, North Carolina State University.

Online decision-making problem requires us to make a sequence of decisions based on incremental information. Common solutions often need to learn a reward model of different actions given the contextual information and then maximize the long-term reward. It is meaningful to know if the posited model is reasonable and how the model performs in the asymptotic sense. We study this problem under the setup of the contextual bandit framework with a linear reward model. The -greedy policy is adopted to address the classic exploration-and-exploitation dilemma. Using the martingale central limit theorem, we show that the online ordinary least squares estimator of model parameters is asymptotically normal. When the linear model is misspecified, we propose the online weighted least squares estimator using the inverse propensity score weighting and also establish its asymptotic normality. Based on the properties of the parameter estimators, we further show that the in-sample inverse propensity weighted value estimator is asymptotically normal. We illustrate our results using simulations and an application to a news article recommendation dataset from Yahoo!.
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http://dx.doi.org/10.1080/01621459.2020.1770098DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7962379PMC
July 2020

Yindan Jiedu Granules, a Traditional Chinese Medicinal Formulation, as a Potential Treatment for Coronavirus Disease 2019.

Front Pharmacol 2020 5;11:634266. Epub 2021 Feb 5.

Center of Integrative Medicine, Beijing Ditan Hospital, Capital Medical University, Beijing, China.

Granules (YDJDG) have been newly prescribed as a Chinese herbal formula. This study aimed to compare the efficacy of YDJDG and lopinavir-ritonavir in the treatment of coronavirus disease 2019 (COVID-19). Overall, 131 patients with COVID-19 were included in this study. In addition to standard care, 60 of these patients received YDJDG (YDJDG group) and 71 received lopinavir-ritonavir (lopinavir-ritonavir group). Propensity score matching (PSM) was used to match the characteristics of individuals in the two groups, while the Kaplan-Meier method was used to compare the proportion recovery observed. Cox analysis revealed that YDJDG and CD4 ≥ 660 cells/µL were independent predictive factors of proportion recovery. At baseline, disease types differed between the YDJDG and lopinavir-ritonavir treatment groups. Furthermore, no significant adverse effects or toxicities relevant to YDJDG were observed. The median recovery time was 21 days in the YDJDG group and 27 days in the lopinavir-ritonavir group. After PSM (1:1), 50 patient pairs, YDJDG vs. lopinavir-ritonavir, were analyzed. In the YDJDG group, the proportion of recovered patients was remarkably higher than that observed in the lopinavir-ritonavir group ( = 0.0013), especially for those presenting mild/moderate disease type and CD4 < 660 cells/µL. In the YDJDG group, the mean duration of fever and pulmonary exudative lesions was significantly shorter than that observed in the lopinavir-ritonavir group ( = 0.0180 and = 0.0028, respectively). YDJDG reveals the potential to hasten the recovery period in COVID-19 patients with mild/moderate disease type or CD4 < 660 cells/µL by shortening the mean duration of fever and pulmonary exudative lesions.
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http://dx.doi.org/10.3389/fphar.2020.634266DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7957926PMC
February 2021

Definition and time course of pericavity edema after minimally invasive endoscopic intracerebral hemorrhage evacuation.

J Neurointerv Surg 2021 Mar 15. Epub 2021 Mar 15.

Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA.

Background: Perihematomal edema (PHE) volume correlates with intracerebral hemorrhage (ICH) volume and is associated with functional outcome. Minimally invasive surgery (MIS) for ICH decreases clot burden and PHE. MIS may therefore alter the time course of PHE, mitigating a critical source of secondary injury.

Objective: To describe a new method for the quantitative measurement of cerebral edema surrounding the evacuated hematoma cavity, termed pericavity edema (PCE), and obtain details of its time course following MIS for ICH.

Methods: The study included 48 consecutive patients presenting with ICH who underwent MIS evacuation. Preoperative and postoperative CT scans were assessed by two independent raters. Hematoma, edema, cavity, and pneumocephalus volumes were calculated using semi-automatic, threshold-guided volume segmentation software (AnalyzePro). Follow-up CT scans at variable delayed time points were available for 36 patients and were used to describe the time course of PCE.

Results: Mean preoperative, postoperative, and delayed PCE were 21.0 mL (SD 15.5), 18.6 mL (SD 11.4), and 18.4 mL (SD 15.5), respectively. The percentage of ICH evacuated correlated significantly with a decrease in postoperative PCE (r=-0.46, p<0.01). Linear regression analysis revealed a significant relation between preoperative hematoma volume and both postoperative PCE (p<0.001) and postoperative relative PCE (p<0.001). The mean peak PCE was 26.4 mL (SD 15.6) and occurred at 6.5 days (SD 4.8) post-ictus. The 2-week postoperative time course of relative PCE did not fluctuate, suggesting stability in edema during the perioperative period surrounding evacuation and up to 2 weeks after the initial bleed.

Conclusions: We present a detailed and accurate method for measuring PCE volume with semi-automatic, threshold-guided segmentation software in the postoperative patient with ICH. Decrease in PCE after MIS evacuation correlated with evacuation percentage, and relative PCE remained stable after minimally invasive endoscopic ICH evacuation.
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http://dx.doi.org/10.1136/neurintsurg-2020-017077DOI Listing
March 2021

The predictive effect of the platelet-to-lymphocyte ratio (PLR) and the neutrophil-to-lymphocyte ratio (NLR) on the risk of death in patients with severe fever with thrombocytopenia syndrome (SFTS): a multi-center study in China.

Ann Transl Med 2021 Feb;9(3):208

Center of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University. Beijing, China.

Background: Severe fever with thrombocytopenia syndrome is caused by infection with the severe fever with thrombocytopenia syndrome virus.

Methods: Between April 2011 and December 2019, data on consecutive patients who were diagnosed with severe fever with thrombocytopenia syndrome were prospectively collected from five medical centers in China. The score of the death risk model was correlated with the platelet-to-lymphocyte ratio and the neutrophil-to-lymphocyte ratio. Multivariable Cox analyses were used to identify the independent factors associated with mortality.

Results: During the study period, 763 patients were diagnosed with severe fever with thrombocytopenia syndrome; 415 of these patients were enrolled in our study. We found that the neutrophil-to-lymphocyte ratio of the group that died was significantly higher on admission (P=0.007) than that of the group that survived, and the neutrophil-to-lymphocyte ratio showed a positive correlation with the score of the death risk model. Multivariate Cox regression suggested that a neutrophil-to-lymphocyte ratio greater than 5.4 was an independent risk factor for survival time (HR=6.767, P=0.011). Platelet-to-lymphocyte ratio did not show a special role in this study.

Conclusions: A neutrophil-to-lymphocyte ratio greater than 5.4 can increase the risk of death and decrease the survival time of patients. In summary, the neutrophil-to-lymphocyte ratio provides a supplementary means for effectively managing severe fever with thrombocytopenia syndrome (SFTS).
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http://dx.doi.org/10.21037/atm-20-4736DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7940944PMC
February 2021

MicroRNA-210 Mediates Hypoxia-Induced Repression of Spontaneous Transient Outward Currents in Sheep Uterine Arteries During Gestation.

Hypertension 2021 Apr 1;77(4):1412-1427. Epub 2021 Mar 1.

From the Lawrence D. Longo, MD, Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, CA.

[Figure: see text].
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http://dx.doi.org/10.1161/HYPERTENSIONAHA.120.16831DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7946727PMC
April 2021

Gestational long-term hypoxia induces metabolomic reprogramming and phenotypic transformations in fetal sheep pulmonary arteries.

Am J Physiol Lung Cell Mol Physiol 2021 05 24;320(5):L770-L784. Epub 2021 Feb 24.

Lawrence D. Longo, MD Center for Perinatal Biology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California.

Gestational long-term hypoxia increases the risk of myriad diseases in infants including persistent pulmonary hypertension. Similar to humans, fetal lamb lung development is susceptible to long-term intrauterine hypoxia, with structural and functional changes associated with the development of pulmonary hypertension including pulmonary arterial medial wall thickening and dysregulation of arterial reactivity, which culminates in decreased right ventricular output. To further explore the mechanisms associated with hypoxia-induced aberrations in the fetal sheep lung, we examined the premise that metabolomic changes and functional phenotypic transformations occur due to intrauterine, long-term hypoxia. To address this, we performed electron microscopy, Western immunoblotting, calcium imaging, and metabolomic analyses on pulmonary arteries isolated from near-term fetal lambs that had been exposed to low- or high-altitude (3,801 m) hypoxia for the latter 110+ days of gestation. Our results demonstrate that the sarcoplasmic reticulum was swollen with high luminal width and distances to the plasma membrane in the hypoxic group. Hypoxic animals were presented with higher endoplasmic reticulum stress and suppressed calcium storage. Metabolically, hypoxia was associated with lower levels of multiple omega-3 polyunsaturated fatty acids and derived lipid mediators (e.g., eicosapentaenoic acid, docosahexaenoic acid, α-linolenic acid, 5-hydroxyeicosapentaenoic acid (5-HEPE), 12-HEPE, 15-HEPE, prostaglandin E3, and 19(20)-epoxy docosapentaenoic acid) and higher levels of some omega-6 metabolites ( < 0.02) including 15-keto prostaglandin E2 and linoleoylglycerol. Collectively, the results reveal broad evidence for long-term hypoxia-induced metabolic reprogramming and phenotypic transformations in the pulmonary arteries of fetal sheep, conditions that likely contribute to the development of persistent pulmonary hypertension.
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http://dx.doi.org/10.1152/ajplung.00469.2020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8174832PMC
May 2021

High detection rate and low efficacy in controlling high blood pressure (≥130/80 mmHg) in the community-based health screening: results from KDSAP.

Eur J Prev Cardiol 2020 Dec 14. Epub 2020 Dec 14.

Renal Division, Department of Internal Medicine, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Avenue, BLI Room 449, Boston, MA 02115, USA.

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http://dx.doi.org/10.1093/eurjpc/zwaa085DOI Listing
December 2020

Iron-Doped MoO Nanosheets for Boosting Nitrogen Fixation to Ammonia at Ambient Conditions.

ACS Appl Mater Interfaces 2021 Feb 7;13(6):7142-7151. Epub 2021 Feb 7.

School of Materials and Energy, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan, China.

Nitrogen can be electrochemically reduced to produce ammonia, which supplies an energy-saving and environmental-benign route at room temperature, but high-efficiency catalysts are sought to reduce the reaction barrier. Here, iron-doped α-MoO nanosheets are thus designed and proposed as potential catalysts for fixing N to NH. The α-MoO band structure is intentionally modulated by the iron doping, which narrows the band gap of α-MoO and turns the semiconductor into a metal-like catalyst. Oxygen vacancies, generated by substituting Mo for Fe anions, are beneficial for nitrogen adsorption at the active sites. In 0.1 M NaSO, the Fe-doped MoO catalyst reached a high faradaic efficiency of 13.3% and an excellent NH yield rate of 28.52 μg h mg at -0.7 V versus reversible hydrogen electrode, superior to most of the other metal-based catalysts. Theoretical calculations confirmed that the N reduction reaction at the Fe-MoO surface followed the distal reaction path.
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http://dx.doi.org/10.1021/acsami.0c19644DOI Listing
February 2021

Functional Outcome After Minimally Invasive Endoscopic Evacuation of Thalamic Intracerebral Hemorrhage.

World Neurosurg 2021 May 3;149:e592-e599. Epub 2021 Feb 3.

Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA.

Background: Intracerebral hemorrhage (ICH) is the most devastating form of stroke, with thalamic hemorrhages carrying the worst outcomes. Minimally invasive (MIS) endoscopic ICH evacuation is a promising new therapy for the condition. However, it remains unclear whether therapy success is location dependent. Here we present long-term functional outcomes after MIS evacuation of spontaneous thalamic hemorrhages.

Methods: Patients presenting to a single urban health system with spontaneous ICH were triaged to a central hospital for management of ICH. Operative criteria for MIS evacuation included hemorrhage volume ≥15 mL, age ≥18, National Institutes of Health Stroke Scale ≥6, and baseline modified Rankin Score (mRS) ≤3. Demographic, radiographic, and clinical data were collected prospectively, and descriptive statistics were performed retrospectively. Functional outcomes were assessed using 6-month mRS scores.

Results: Endoscopic ICH evacuation was performed on 21 patients. Eleven patients had hemorrhage confined to the thalamus, whereas 10 patients had hemorrhages in the thalamus and surrounding structures. Eighteen patients (85.7%) had intraventricular extension. The average preoperative volume was 39.8 mL (standard deviation [SD]: 31.5 mL) and postoperative volume was 3.8 mL (SD: 6.1 mL), resulting in an average evacuation rate of 91.4% (SD: 11.1%). One month after hemorrhage, 2 patients (9.5%) had expired and all other patients remained functionally dependent (90.5%). At 6-month follow-up, 4 patients (19.0%) had improved to a favorable outcome (mRS ≤ 3).

Conclusion: Among patients with ICH undergoing medical management, those with thalamic hemorrhages have especially poor outcomes. This study suggests that MIS evacuation can be safely performed in a thalamic population. It also presents long-term functional outcomes that can aid in planning randomization schemes or subgroup analyses in future MIS evacuation clinical trials.
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http://dx.doi.org/10.1016/j.wneu.2021.01.128DOI Listing
May 2021

Development of a novel deployable arm for natural orifice transluminal endoscopic surgery.

Int J Med Robot 2021 Jun 28;17(3):e2232. Epub 2021 Mar 28.

School of Control Science and Engineering, Shandong University, Jinan, China.

Background: Natural orifice transluminal endoscopic surgery (NOTES) is aided by the instrument channel of an endoscope. Limited by the diameter of the endoscope, the construction of the operation triangle is affected. This paper presents a deployable arm that can increase the distance between the arms.

Methods: The manipulation arm is composed of a continuum arm and a deployable arm. The deployable arm can be locked by a stay cable and a mechanical structure. The angle between the end-effectors and the common workspace of the two manipulation arms are comprehensively analysed. Through experiments, the design parameters are validated and justified.

Results: The experiment shows that the deployment arm can maintain the deformation within 3.5 mm under a 300 g load, and the angle between the two end-effectors can be maintained within the range of [88°, 110°].

Conclusions: The novel deployment arms enlarge the angle between the end effectors, which significantly improves the flexibility of the arms.
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http://dx.doi.org/10.1002/rcs.2232DOI Listing
June 2021

Interhospital Transfer of Intracerebral Hemorrhage Patients Undergoing Minimally Invasive Surgery: The Experience of a New York City Hospital System.

World Neurosurg 2021 04 8;148:e390-e395. Epub 2021 Jan 8.

Icahn School of Medicine at Mount Sinai, Department of Neurosurgery, New York, New York, USA. Electronic address:

Objective: The impact of interhospital transfer (IHT) on outcomes of patients with intracerebral hemorrhage (ICH) has not been well studied. We seek to describe the protocolized IHT and systems of care approach of a New York City hospital system, where ICH patients undergoing minimally invasive surgery (MIS) are transferred to a dedicated ICH center.

Methods: We retrospectively reviewed 100 consecutively admitted patients with spontaneous ICH. We gathered information on demographics, variables related to IHT, clinical and radiographic characteristics, and details about the clinical course and outpatient follow-up. We grouped patients into 2 cohorts: those admitted through IHT and those directly admitted through the emergency department. Primary outcome was good functional outcome at 6 months, defined as modified Rankin Scale score 0-3.

Results: Of 100 patients, 89 underwent IHT and 11 were directly admitted. On multivariable analysis, there were no significant differences in 6-month functional outcome between the 2 cohorts. All transfers were managed by a system-wide transfer center and 24/7 hotline for neuroemergencies. An ICH-specific IHT protocol was followed, in which a neurointensivist provided recommendations for stabilizing patients for transfer. Average transfer time was 199.7 minutes and average distance travelled was 13.6 kilometers.

Conclusions: In our hospital system, a centralized approach to ICH management and a dedicated ICH center increased access to specialist services, including MIS. Most patients undergoing MIS were transferred from outside hospitals, which highlights the need for additional studies and descriptions of experiences to further elucidate the impact of and best protocols for the IHT of ICH patients.
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http://dx.doi.org/10.1016/j.wneu.2020.12.163DOI Listing
April 2021

High prevalence of occult thrombosis in cases of mild/moderate COVID-19.

Int J Infect Dis 2021 Mar 19;104:77-82. Epub 2020 Dec 19.

The Infectious Disease Diagnostic, Therapeutic and Research Centers, Beijing Ditan Hospital, Capital Medical University, Beijing, China. Electronic address:

Background And Purpose: An increasing number of reports have observed thrombosis in severe cases of COVID-19. The aim of this study was to evaluate the incidence of thromboembolism in mild/moderate cases of COVID-19. All of the patients had normal coagulation tests and none had any overt thrombotic complications. Our findings indicate that it is important to screen the thrombotic status of cases with mild/moderate COVID-19.

Methods: Between 11 June and 8 July 2020, 23 patients with mild/moderate COVID-19 pneumonia consented to having computed tomography pulmonary angiography (CPTA) and computed tomography venography (CTV) scans of the lungs and extremity veins. Doppler ultrasound (DUS) was also performed in all patients for screening. The incidence, clinical manifestations, laboratory examinations, imaging features, and prognosis, of patients with venous thromboembolism (VTE) were analyzed and compared with those of patients with COVID-19 pneumonia without VTE.

Results: Nineteen patients (82.6%) had VTE, mainly distal limb thrombosis. Only one of the VTE patients was positive when screened by DUS; the other VTE patients were negative by DUS. All of the mild/moderate patients with VTE were screened by CTPA + CTV. Blood tests for inflammatory, coagulation, and biochemical, parameters were all within the normal range, except for WBC and LDH.

Conclusions: When using CTV screening for DVT, we found that the incidence of thrombosis in patients with mild/moderate COVID-19 markedly increased to 82.6% (19/23). Screening for thrombosis is therefore important in patients with COVID-19. CTV is more sensitive than DUS for the detection of thrombosis. More research is now needed to evaluate the significance of thrombosis in COVID-19 pneumonia.
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http://dx.doi.org/10.1016/j.ijid.2020.12.042DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7749732PMC
March 2021

A Sparse Random Projection-based Test for Overall Qualitative Treatment Effects.

J Am Stat Assoc 2020 19;115(531):1201-1213. Epub 2019 Jun 19.

Department of Statistics, North Carolina State University, Raleigh, NC 27695.

In contrast to the classical "one size fits all" approach, precision medicine proposes the customization of individualized treatment regimes to account for patients' heterogeneity in response to treatments. Most of existing works in the literature focused on estimating optimal individualized treatment regimes. However, there has been less attention devoted to hypothesis testing regarding the existence of overall qualitative treatment effects, especially when there is a large number of prognostic covariates. When covariates don't have qualitative treatment effects, the optimal treatment regime will assign the same treatment to all patients regardless of their covariate values. In this paper, we consider testing the overall qualitative treatment effects of patients' prognostic covariates in a high dimensional setting. We propose a sample splitting method to construct the test statistic, based on a nonparametric estimator of the contrast function. When the dimension of covariates is large, we construct the test based on sparse random projections of covariates into a low-dimensional space. We prove the consistency of our test statistic. In the regular cases, we show the asymptotic power function of our test statistic is asymptotically the same as the "oracle" test statistic which is constructed based on the "optimal" projection matrix. Simulation studies and real data applications validate our theoretical findings.
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http://dx.doi.org/10.1080/01621459.2019.1604368DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7730172PMC
June 2019

Degradation of BTEXS with stable and pH-insensitive iron-manganese modified biochar from post pyrolysis.

Chemosphere 2021 Jan 28;263:128092. Epub 2020 Aug 28.

School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China.

An efficient iron-manganese modified biochar (FMBC) was successfully synthesized as a heterogeneous Fenton-like catalyst through easy post-modification and applied for degradation of benzene, toluene, ethylbenzene, xylene isomers (ortho, para, and meta), and styrene (BTEXS) in the presence of HO. The catalyst was characterized by Brunauer-Emmett-Teller method, scanning electron microscopy, and X-ray photoelectron spectrometry. The effects of HO concentration, FMBC dose, and initial pH on BTEXS degradation were also investigated. Results showed that degradation efficiency of FMBC for individual BTEXS varied from 83.05% to 94.12% in 3 h. Kinetic analysis showed that a first-order kinetic model with respect to BTEXS concentration could be used to explain the BTEXS degradation for FMBC/HO system. The degradation reaction was more suitable in a wide pH range (3-10) than those in previous studies, thereby overcoming the low-efficiency problem of conventional Fenton reaction at high pH. Moreover, the doses of FMBC and HO are a crucial factor affecting BTEXS degradation. Radical scavenger experiments revealed that ∙OH, ∙O, and O participated in the degradation process, and ∙OH was the major contributor. The synthesized catalyst is durable with stable BTEXS removal efficiency after seven consecutive cycles. The removal efficiency of BTEXS by FMBC in produced water reached 93.23% in 12 h, indicating FMBC has practical value.
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http://dx.doi.org/10.1016/j.chemosphere.2020.128092DOI Listing
January 2021
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