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1.
ACS Mater Au ; 4(3): 258-273, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38737116

ABSTRACT

Electroactive materials are central to myriad applications, including energy storage, sensing, and catalysis. Compared to traditional inorganic electrode materials, redox-active organic materials such as porous organic polymers (POPs) and covalent organic frameworks (COFs) are emerging as promising alternatives due to their structural tunability, flexibility, sustainability, and compatibility with a range of electrolytes. Herein, we discuss the challenges and opportunities available for the use of redox-active organic materials in organoelectrochemistry, an emerging area in fine chemical synthesis. In particular, we highlight the utility of organic electrode materials in photoredox catalysis, electrochemical energy storage, and electrocatalysis and point to new directions needed to unlock their potential utility for organic synthesis. This Perspective aims to bring together the organic, electrochemistry, and polymer communities to design new heterogeneous electrocatalysts for the sustainable synthesis of complex molecules.

2.
Front Biosci (Landmark Ed) ; 29(4): 141, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38682199

ABSTRACT

Pericytes, a specific type of mesenchymal cell that surround the basement membrane of pulmonary venules and capillaries. They are crucial pathological features observed in individuals with the severe lung disease of pulmonary fibrosis (PF). The presence of pericytes leads to inflammation and fibrosis in the lung interstitium and alveolar space due to the release of various cytokines and chemokines. Pericytes also stimulate the proliferation and activation of fibroblasts, thereby promoting the progression of PF. Previous studies examining the mechanism of action of pericytes have primarily focused on cell signal transduction pathways, cell growth and death processes, and the synthesis and breakdown of extracellular matrix (ECM). Notably, the transforming growth factor-ß (TGF-ß) and Wnt signaling pathways have been associated with the action of pericytes in driving the progression of PF. It is therefore clear that pericytes play an essential role in the development of PF, while also offering possible avenues for targeted therapeutic intervention against this condition. The current article provides a comprehensive review on how pericytes contribute to inflammatory responses, as well as their importance for understanding the mechanism of PF. In addition, this review discusses the potential use of pericyte-targeted approaches for the treatment of patients affected by this debilitating lung disease.


Subject(s)
Pericytes , Pulmonary Fibrosis , Pericytes/pathology , Pericytes/metabolism , Humans , Pulmonary Fibrosis/pathology , Pulmonary Fibrosis/metabolism , Animals , Transforming Growth Factor beta/metabolism , Signal Transduction , Extracellular Matrix/metabolism , Wnt Signaling Pathway
3.
Angew Chem Int Ed Engl ; 62(40): e202310246, 2023 Oct 02.
Article in English | MEDLINE | ID: mdl-37559156

ABSTRACT

Single-electron transfer (SET) plays a critical role in many chemical processes, from organic synthesis to environmental remediation. However, the selective reduction of inert substrates (Ep/2 <-2 V vs Fc/Fc+ ), such as ubiquitous electron-neutral and electron-rich (hetero)aryl chlorides, remains a major challenge. Current approaches largely rely on catalyst photoexcitation to reach the necessary deeply reducing potentials or suffer from limited substrate scopes. Herein, we demonstrate that cumulenes-organic molecules with multiple consecutive double bonds-can function as catalytic redox mediators for the electroreductive radical borylation of (hetero)aryl chlorides at relatively mild cathodic potentials (approximately -1.9 V vs. Ag/AgCl) without the need for photoirradiation. Electrochemical, spectroscopic, and computational studies support that step-wise electron transfer from reduced cumulenes to electron-neutral chloroarenes is followed by thermodynamically favorable mesolytic cleavage of the aryl radical anion to generate the desired aryl radical intermediate. Our findings will guide the development of other sustainable, purely electroreductive radical transformations of inert molecules using organic redox mediators.

4.
Mol Med ; 29(1): 32, 2023 03 14.
Article in English | MEDLINE | ID: mdl-36918759

ABSTRACT

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a condition that may cause persistent pulmonary damage. The transformation of pericytes into myofibroblasts has been recognized as a key player during IPF progression. This study aimed to investigate the functions of lncRNA growth arrest-specific transcript 5 (GAS5) in myofibroblast transformation during IPF progression. METHODS: We created a mouse model of pulmonary fibrosis (PF) via intratracheal administration of bleomycin. Pericytes were challenged with exogenous transforming growth factor-ß1 (TGF-ß1). To determine the expression of target molecules, we employed quantitative reverse transcription-polymerase chain reaction, Western blotting, and immunohistochemical and immunofluorescence staining. The pathological changes in the lungs were evaluated via H&E and Masson staining. Furthermore, the subcellular distribution of GAS5 was examined using FISH. Dual-luciferase reporter assay, ChIP, RNA pull-down, and RIP experiments were conducted to determine the molecular interaction. RESULTS: GAS5 expression decreased whereas PDGFRα/ß expression increased in the lungs of IPF patients and mice with bleomycin-induced PF. The in vitro overexpression of GAS5 or silencing of PDGFRα/ß inhibited the TGF-ß1-induced differentiation of pericytes to myofibroblasts, as evidenced by the upregulation of pericyte markers NG2 and desmin as well as downregulation of myofibroblast markers α-SMA and collagen I. Further mechanistic analysis revealed that GAS5 recruited KDM5B to promote H3K4me2/3 demethylation, thereby suppressing PDGFRα/ß expression. In addition, KDM5B overexpression inhibited pericyte-myofibroblast transformation and counteracted the promotional effect of GAS5 knockdown on pericyte-myofibroblast transformation. Lung fibrosis in mice was attenuated by GAS5 overexpression but promoted by GAS5 deficiency. CONCLUSION: GAS5 represses pericyte-myofibroblast transformation by inhibiting PDGFRα/ß expression via KDM5B-mediated H3K4me2/3 demethylation in IPF, identifying GAS5 as an intervention target for IPF.


Subject(s)
Idiopathic Pulmonary Fibrosis , RNA, Long Noncoding , Animals , Mice , Bleomycin/adverse effects , Demethylation , DNA-Binding Proteins/metabolism , Fibroblasts/metabolism , Idiopathic Pulmonary Fibrosis/chemically induced , Idiopathic Pulmonary Fibrosis/genetics , Idiopathic Pulmonary Fibrosis/metabolism , Jumonji Domain-Containing Histone Demethylases/metabolism , Lung , Mice, Inbred C57BL , Myofibroblasts/metabolism , Pericytes/metabolism , Pericytes/pathology , Receptor, Platelet-Derived Growth Factor alpha/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Transforming Growth Factor beta1/metabolism
5.
Biomacromolecules ; 23(12): 5213-5224, 2022 Dec 12.
Article in English | MEDLINE | ID: mdl-36382861

ABSTRACT

Poly(α-methylene ester)s are an attractive type of functional aliphatic polyesters that represent a platform for the fabrication of various biodegradable and biomedical polymers. Herein, we report the controlled ring-opening polymerization (ROP) of a seven-membered α-methylene lactone (3-methylene-1,5-dioxepan-2-one, MDXO) that was synthesized based on the Baylis-Hillman reaction. The chemoselective ROP of MDXO was catalyzed by diphenyl phosphate (DPP) at 60 °C or stannous octoate (Sn(Oct)2) at 130 °C, generating α-methylene-containing polyester (PMDXO) with a linear structure and easily tunable molar mass. The ring-opening copolymerization of MDXO with ε-caprolactone or 1,5-dioxepan-2-one was also performed under the catalysis of DPP or Sn(Oct)2 to afford copolymers with different compositions and sequence structures that are influenced by the kinds of monomers and catalysts. PMDXO is a slowly crystallizable polymer with a glass transition temperature of ca. -33 °C, and its melting temperature and enthalpy are significantly influenced by the thermal history. The thermal properties of the copolymers are dependent on their composition and sequence structure. Finally, the post-modification of PMDXO based on the thiol-Michael addition reaction was briefly explored using triethylamine as a catalyst. Given the optimized condition, PMDXO could be dually modified to afford biodegradable polyesters with different functionalities.


Subject(s)
Biocompatible Materials , Esters , Biocompatible Materials/chemistry , Polyesters/chemistry , Polymers/chemistry
6.
Front Public Health ; 10: 953441, 2022.
Article in English | MEDLINE | ID: mdl-36033785

ABSTRACT

Background: The quality of bowel preparation is an important factor in the success of colonoscopy. However, the quality of bowel preparation is often affected by multiple factors. The main objective of this study was to explore the specific factors that affect the quality of bowel preparation. Methods: Patients were consecutively recruited from the gastroenterology department in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology in Wuhan from May 2018 to December 2018. All patients were undergoing colonoscopy. Bowel preparation was evaluated by the Ottawa Bowel preparation Scale (OBPS) and all patients were categorized into 2 groups according to the OBPS. Multivariate analysis was conducted to identify the factors associated with bowel preparation quality. Results: A total of 910 patients were included in the analysis with an average age of 48.62 ± 13.57 years. Patient source (P < 0.001) and the preparation method (P = 0.029) were correlated with OBPS adequacy. In addition, after stratified by age, preparation method (P = 0.022) was a significant factor among patients under 50 years old; whereas waiting time (P = 0.005) was a significant factor among patients over 50 years old. Conclusion: Bowel preparation should be tailored based on the age of the patients to determine the most appropriate plan, including the most appropriate waiting time and the most appropriate purgative combination. Doctors should also focus more on the quality of bowel preparation in inpatients, who are more likely than outpatients to have an inadequate bowel preparation.


Subject(s)
Cathartics , Colonoscopy , Adult , China , Cross-Sectional Studies , Humans , Middle Aged , Prospective Studies
7.
J Clin Psychol ; 77(7): 1700-1714, 2021 07.
Article in English | MEDLINE | ID: mdl-33951200

ABSTRACT

OBJECTIVE: This study established cognitive vulnerability of anxiety symptoms among high school students. METHOD: A total of 72 grade 9-11 students completed measures on levels of anxiety sensitivity (AS), selective attentional processing, and anxiety symptoms annually between 2016 and 2018. RESULTS: Latent class growth analysis (unconditional model) showed a four-class model: High (stable) (6.94%), low (stable) (11.11%), medium (decreasing) (61.11%), and medium (increasing) (20.83%). The conditioned model controlling for the physical-concerns dimension of AS and negative attentional bias demonstrated that a two-class model consisted of a low anxiety class (n = 59, 81.9%) and a high anxiety class (n = 13, 18.1%) provided the best fit for the data. Negative attentional bias is a significant factor related to the development of anxiety trajectories. CONCLUSION: Attentional bias modification to disengage from negative stimuli may serve as a potential target of intervention to reduce chronic anxiety among high school students.


Subject(s)
Anxiety , Attentional Bias , Adolescent , Anxiety/epidemiology , China , Cognition , Humans , Longitudinal Studies
8.
Support Care Cancer ; 29(7): 4045-4053, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33404810

ABSTRACT

This study examined the long-term trajectory patterns of anxiety in breast cancer survivors and identified its predicting variables, especially the type of coping profile. Eighty-one patients who completed all four questionnaires from the 10-year study were included in the analysis. Anxiety scores from the Hospital Anxiety and Depression Scale were used in latent class growth analysis to chart the anxiety trajectory of cancer survivors. Demographic variables, clinical variables, depression level, and coping profiles (adaptive versus maladaptive) were used as predictors. Our study identified a two-class model of long-term anxiety trajectory among breast cancer survivors, with a resistant group (85.2%) and a distress group (14.8%). Demographic and clinical variables were not associated with anxiety trajectory paths. On the other hand, maladaptive coping characterized by higher scores in helplessness/hopelessness, cognitive avoidance, and anxious preoccupation, and lower scores in fighting spirit and fatalism in the Mini-MAC was a significant predictor of distressed anxiety. Coping profiles identified using the Mini-MAC were predictive of long-term anxiety trajectory among breast cancer survivors in our survey. Early interventions on coping with cancer could reduce long-term anxiety problems.


Subject(s)
Adaptation, Psychological , Anxiety/psychology , Breast Neoplasms/psychology , Cancer Survivors/psychology , Psychometrics/methods , Adult , Aged , Anxiety Disorders/psychology , Female , Humans , Middle Aged , Self Concept , Surveys and Questionnaires
9.
J Am Chem Soc ; 142(51): 21272-21278, 2020 12 23.
Article in English | MEDLINE | ID: mdl-33290654

ABSTRACT

The construction of C(sp3)-Si bonds is important in synthetic, medicinal, and materials chemistry. In this context, reactions mediated by silyl radicals have become increasingly attractive but methods for accessing these intermediates remain limited. We present a new strategy for silyl radical generation via electroreduction of readily available chlorosilanes. At highly biased potentials, electrochemistry grants access to silyl radicals through energetically uphill reductive cleavage of strong Si-Cl bonds. This strategy proved to be general in various alkene silylation reactions including disilylation, hydrosilylation, and allylic silylation under simple and transition-metal-free conditions.


Subject(s)
Chlorine/chemistry , Silanes/chemistry , Silicon/chemistry , Electrochemistry , Oxidation-Reduction , Thermodynamics
10.
JMIR Form Res ; 4(10): e17895, 2020 Oct 05.
Article in English | MEDLINE | ID: mdl-33016883

ABSTRACT

BACKGROUND: Depression during pregnancy and in the postpartum period is associated with poor outcomes for women and their children. Although effective interventions exist for common mental disorders that occur during pregnancy and the postpartum period, most cases in low- and middle-income countries go untreated because of a lack of trained professionals. Task-sharing models such as the Thinking Healthy Program have shown potential in feasibility and efficacy trials as a strategy for expanding access to treatment in low-resource settings; however, there are significant barriers to scale-up. We address this gap by adapting Thinking Healthy for automated delivery via a mobile phone. This new intervention, Healthy Moms, uses an existing artificial intelligence system called Tess (Zuri in Kenya) to drive conversations with users. OBJECTIVE: This prepilot study aims to gather preliminary data on the Healthy Moms perinatal depression intervention to learn how to build and test a more robust service. METHODS: We conducted a single-case experimental design with pregnant women and new mothers recruited from public hospitals outside of Nairobi, Kenya. We invited these women to complete a brief, automated screening delivered via text messages to determine their eligibility. Enrolled participants were randomized to a 1- or 2-week baseline period and then invited to begin using Zuri. We prompted participants to rate their mood via SMS text messaging every 3 days during the baseline and intervention periods, and we used these preliminary repeated measures data to fit a linear mixed-effects model of response to treatment. We also reviewed system logs and conducted in-depth interviews with participants to study engagement with the intervention, feasibility, and acceptability. RESULTS: We invited 647 women to learn more about Zuri: 86 completed our automated SMS screening and 41 enrolled in the study. Most of the enrolled women submitted at least 3 mood ratings (31/41, 76%) and sent at least 1 message to Zuri (27/41, 66%). A third of the sample engaged beyond registration (14/41, 34%). On average, women who engaged post registration started 3.4 (SD 3.2) Healthy Moms sessions and completed 3.1 (SD 2.9) of the sessions they started. Most interviewees who tried Zuri reported having a positive attitude toward the service and expressed trust in Zuri. They also attributed positive life changes to the intervention. We estimated that using this alpha version of Zuri may have led to a 7% improvement in mood. CONCLUSIONS: Zuri is feasible to deliver via SMS and was acceptable to this sample of pregnant women and new mothers. The results of this prepilot study will serve as a baseline for future studies in terms of recruitment, data collection, and outcomes. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/11800.

11.
Org Lett ; 22(10): 3825-3829, 2020 May 15.
Article in English | MEDLINE | ID: mdl-32378901

ABSTRACT

We describe an unprecedented dual C-H functionalization of indolin-2-one via an oxidative C(sp3)-H/N-H/X-H (X = N, C, S) cross-coupling protocol, which is catalyzed by a simple iron salt under mild and ligand-free conditions and employs air (molecular oxygen) as the terminal oxidant. This method is readily applicable for the construction of tetrasubstituted carbon centers from methylenes and provides a wide variety of spiro N-heterocyclic oxindoles.

12.
J Health Psychol ; 25(13-14): 2233-2243, 2020.
Article in English | MEDLINE | ID: mdl-30080097

ABSTRACT

A total of 84 breast cancer survivors completed a package of psychological inventories in 2009 (Time 1), 2012 (Time 2), and 2016 (Time 3). Latent class growth analysis revealed three posttraumatic growth trajectory patterns: distressed posttraumatic growth (n = 5, 6.7%), illusory posttraumatic growth (n = 42, 56.0%), and constructive posttraumatic growth (n = 28, 37.3%). Women with more frequent use of helplessness-hopelessness coping and lower depression levels at Time 1 were more likely to display an illusory than a constructive posttraumatic growth trajectory pattern. Illusory posttraumatic growth might represent a form of coping rather than authentic positive changes. Researchers and clinicians should understand different patterns of posttraumatic growth.


Subject(s)
Breast Neoplasms , Cancer Survivors , Posttraumatic Growth, Psychological , Stress Disorders, Post-Traumatic , Adaptation, Psychological , Breast Neoplasms/psychology , Female , Humans , Survivors
13.
JMIR Res Protoc ; 8(4): e11800, 2019 Apr 29.
Article in English | MEDLINE | ID: mdl-31033448

ABSTRACT

BACKGROUND: Depression during pregnancy and in the postpartum period is associated with a number of poor outcomes for women and their children. Although effective interventions exist for common mental disorders that occur during pregnancy and the postpartum period, most cases in low- and middle-income countries go untreated because of a lack of trained professionals. Task-sharing models such as the Thinking Healthy Program have shown great potential in feasibility and efficacy trials as a strategy for expanding access to treatment in low-resource settings, but there are significant barriers to scale-up. We are addressing this gap by adapting Thinking Healthy for automated delivery via a mobile phone. This new intervention, Healthy Moms, uses an existing artificial intelligence system called Tess (Zuri in Kenya) to drive conversations with users. OBJECTIVE: The objective of this pilot study is to test the Healthy Moms perinatal depression intervention using a single-case experimental design with pregnant women and new mothers recruited from public hospitals outside of Nairobi, Kenya. METHODS: We will invite patients to complete a brief, automated screening delivered via text messages to determine their eligibility. Enrolled participants will be randomized to a 1- or 2-week baseline period and then invited to begin using Zuri. Participants will be prompted to rate their mood via short message service every 3 days during the baseline and intervention periods. We will review system logs and conduct in-depth interviews with participants to study engagement with the intervention, feasibility, and acceptability. We will use visual inspection, in-depth interviews, and Bayesian estimation to generate preliminary data about the potential response to treatment. RESULTS: Our team adapted the intervention content in April and May 2018 and completed an initial prepilot round of formative testing with 10 women from a private maternity hospital in May and June. In preparation for this pilot study, we used feedback from these users to revise the structure and content of the intervention. Recruitment for this protocol began in early 2019. Results are expected toward the end of 2019. CONCLUSIONS: The main limitation of this pilot study is that we will recruit women who live in urban and periurban centers in one part of Kenya. The results of this study may not generalize to the broader population of Kenyan women, but that is not an objective of this phase of work. Our primary objective is to gather preliminary data to know how to build and test a more robust service. We are working toward a larger study with a more diverse population. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/11800.

14.
PLoS One ; 13(9): e0203883, 2018.
Article in English | MEDLINE | ID: mdl-30208105

ABSTRACT

BACKGROUND: Jaw correction surgery can cause significant psychosocial impacts on patients. This prospective study investigated the longitudinal changes of psychosocial characteristics of patients with dentofacial deformities after jaw correction surgery and the factors that predict the psychological resilience in Hong Kong Chinese undergoing jaw correction surgery. METHODS: A longitudinal cohort study was conducted on 92 Hong Kong Chinese patients (32 males, 60 females; mean age = 24.75 ± 5.65 years), who had jaw correction surgery as treatment for their dentofacial deformities, from 1st June 2011 to 30th June 2015. Self-completed psychological inventories including Brief Symptom Inventory, Life Orientation Test, and the Adult Trait Hope Scale were used to measure distress, optimism, and hope levels respectively. Patients completed the inventories in five time points: the surgical consent signing day (usually two to three months before the surgery) (T1); one day before operation (T2), first to second post-operative week (T3), third post-operative month (T4) and sixth post-operative month (T5). RESULTS: Latent class growth analysis revealed two outcome trajectory classes: a resilience trajectory (n = 45, 48.9%) and a chronic dysfunction trajectory (n = 14, 15.2%). Another 33 (35.9%) showed erratic trajectory patterns that would not be classified into any categories. The psychological distress levels of patients in the resilience trajectory group, on average, were below the clinical threshold of the Brief Symptom Inventory at all time points. However, the opposite result was obtained for patients in the chronic dysfunctional group. Patients exhibiting a resilience trajectory pattern, when compared to those showing a chronic dysfunction pattern, had higher optimism (t(57) = 3.69, p < .0001) and hope (t(57) = 2.46, p < .05) levels at T1. Logistic regression analyses were conducted to compare the relative power of optimism and hope levels at T1 to predict resilience or chronic dysfunctional group membership. A test of the full model against a constant only model was statistically significant (χ2(2) = 24.096, p < .01). Preoperative baseline optimism (B = -.276, p < .05) but not hope (B = -.25, ns) was a significant variable to classify the outcome trajectories for psychological distress. CONCLUSIONS: Most patients were resilient to dentofacial deformities jaw correction surgery. About 15% exhibited a chronic distress pattern. An optimistic view about the surgery may enhance resilience. Pre-surgical counselling or educational sessions to facilitate a realistic positive outlook about the operation would be beneficial.


Subject(s)
Orthognathic Surgical Procedures/psychology , Psychology/methods , Stress, Psychological/psychology , Adaptation, Psychological/classification , Adult , Asian People/psychology , Depression/psychology , Female , Hong Kong , Hope , Humans , Longitudinal Studies , Male , Optimism/psychology , Orthognathic Surgery/methods , Prospective Studies , Psychology/classification , Psychosocial Support Systems , Resilience, Psychological/classification , Self Report , Young Adult
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