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1.
Angew Chem Int Ed Engl ; : e202407163, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38864252

ABSTRACT

Electrosynthesis of hydrogen peroxide (H2O2) based on proton exchange membrane (PEM) reactor represents a promising approach to industrial-level H2O2 production, while it is hampered by the lack of high-efficiency electrocatalysts in acidic medium. Herein, we present a strategy for the specific oxygen functional group (OFG) regulation to promote the H2O2 selectivity up to 92% in acid on cobalt-porphyrin molecular assembled with reduced graphene oxide. In-situ X-ray adsorption spectroscopy, in-situ Raman spectroscopy and Kelvin probe force microscopy combined with theoretical calculation unravel that different OFGs exert distinctive regulation effects on the electronic structure of Co center through either remote (carboxyl and epoxy) or vicinal (hydroxyl) interaction manners, thus leading to the opposite influences on the promotion in 2e- ORR selectivity. As a consequence, the PEM electrolyzer integrated with the optimized catalyst can continuously and stably produce the high-concentration of ca. 7 wt% pure H2O2 aqueous solution at 400 mA cm-2 over 200 h with a cell voltage as low as ca. 2.1 V, suggesting the application potential in industrial-scale H2O2 electrosynthesis.

2.
Article in English | MEDLINE | ID: mdl-38829162

ABSTRACT

Purpose: To evaluate the therapeutic efficacy of topical application of a neurokinin-1 receptor (NK1R) antagonist in a rabbit model of nonallergic ocular redness. Methods: Nonallergic ocular redness was induced in rabbits by a single, topical application of dapiparzole hydrochloride eye drops (0.5%, 1%, 2%, or 5%). The NK1R antagonist L-703,606 was topically applied to the eye at the same time of induction or 20 min after induction, and phosphate buffered saline (PBS) treatment served as the control. Superior bulbar conjunctival images were taken every 30 s for the first 2 min, followed by every 4 min for 8 min, and then every 10 min until 1 h. The severity of ocular redness was evaluated on the images using ImageJ-based ocular redness index (ORI) calculations. Results: The ORI scores were significantly increased after the application of 0.5%, 1%, 2%, or 5% dapiparzole at each time point evaluated, with the most severe redness induced by the 5% dapiprazole that led to a maximal mean increase in ORI score of 14 at 20 min post-induction and thus used for subsequent evaluation of therapeutic efficacy of NK1R antagonism. Topical L-703,606, when applied at the same time as dapiprazole induction, significantly suppressed the increase of ORI scores at all time points (∼40% decrease). Furthermore, when applied at 20 min after dapiprazole induction, L-703,606 rapidly and effectively suppressed the increase of ORI scores at 30, 40, 50, and 60 min (∼30% decrease). Conclusions: Topical blockade of NK1R effectively prevents and alleviates nonallergic ocular redness in a novel animal model.

3.
J Leukoc Biol ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38916986

ABSTRACT

Substance P (SP) is a neuropeptide expressed by nerves and an array of cells that serves as a critical mediator of neuroinflammation. Our recent work has demonstrated that blocking the preferred receptor for SP, neurokinin-1 receptor (NK1R), effectively suppresses the induction of acute dry eye disease (DED) by preserving regulatory T cell (Treg) function, while inhibiting antigen-presenting cell (APC) maturation and subsequent generation of effector Th17 cells (eTh17). Clinically, DED is a chronic disorder characterized by sustained ocular surface inflammation which is mediated by long-lived memory Th17 cells (mTh17) demonstrated in our well-established chronic DED model. The present study aimed to further understand the function of SP in the chronic phase of DED and its role in regulating the underlying pathogenic mTh17. In vitro culture of effector T cells isolated from acute DED with SP led to an enhanced conversion of eTh17 to mTh17, while culturing memory T cells isolated from chronic DED with SP effectively preserved the mTh17 cells. In contrast, the addition of an NK1R antagonist in the cultures abolished the SP-mediated effects. Furthermore, in vivo treatment with the NK1R antagonist during the resolution phase of acute DED significantly suppressed mTh17 generation, and treatment in the chronic phase of DED disrupted the maintenance of mTh17. Taken together, our results demonstrate that increased expression of SP promotes mTh17 generation and maintenance in chronic DED, and thus blockade of SP represents a novel promising mTh17-targeting strategy in treating chronic ocular surface inflammation.

4.
PLoS One ; 19(5): e0300747, 2024.
Article in English | MEDLINE | ID: mdl-38696378

ABSTRACT

We investigate the impact of left-behind experiences on the urban identity of new-generation migrant workers using data from the 2017 China Migrants Dynamic Survey. The results show the following: (1) The left-behind experience is an important factor undermining the urban identity of new-generation migrant workers, and the conclusion remains consistent after robustness checks, such as propensity score matching. (2) Left-behind experiences of both parents away from home had the most significant negative impact on urban identity. (3) The results of the mechanism tests indicate that the left-behind experience exerts an adverse impact on urban identity through the pathways of poorer physical health, more frequent migration, more challenging job search, and stronger dependence on preexisting social networks. The findings of this study also offer policy suggestions for promoting the urban identity of new-generation migrant workers.


Subject(s)
Transients and Migrants , Urban Population , Humans , Transients and Migrants/psychology , Male , China , Adult , Female , Surveys and Questionnaires , Young Adult , Middle Aged
5.
J Thromb Haemost ; 22(6): 1727-1741, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38537781

ABSTRACT

BACKGROUND: Megakaryocytes (MKs) are polyploid cells responsible for producing ∼1011 platelets daily in humans. Unraveling the mechanisms regulating megakaryopoiesis holds the promise for the production of clinical-grade platelets from stem cells, overcoming significant current limitations in platelet transfusion medicine. Previous work identified that loss of the epigenetic regulator SET domain containing 2 (SETD2) was associated with an increased platelet count in mice. However, the role of SETD2 in megakaryopoiesis remains unknown. OBJECTIVES: Here, we examined how SETD2 regulated MK development and platelet production using complementary murine and human systems. METHODS: We manipulated the expression of SETD2 in multiple in vitro and ex vivo models to assess the ploidy of MKs and the function of platelets. RESULTS: The genetic ablation of Setd2 increased the number of high-ploidy bone marrow MKs. Peripheral platelet counts in Setd2 knockout mice were significantly increased ∼2-fold, and platelets exhibited normal size, morphology, and function. By knocking down and overexpressing SETD2 in ex vivo human cell systems, we demonstrated that SETD2 negatively regulated MK polyploidization by controlling methylation of α-tubulin, microtubule polymerization, and MK nuclear division. Small-molecule inactivation of SETD2 significantly increased the production of high-ploidy MKs and platelets from human-induced pluripotent stem cells and cord blood CD34+ cells. CONCLUSION: These findings identify a previously unrecognized role for SETD2 in regulating megakaryopoiesis and highlight the potential of targeting SETD2 to increase platelet production from human cells for transfusion practices.


Subject(s)
Blood Platelets , Histone-Lysine N-Methyltransferase , Megakaryocytes , Mice, Knockout , Polyploidy , Thrombopoiesis , Tubulin , Megakaryocytes/metabolism , Megakaryocytes/cytology , Animals , Blood Platelets/metabolism , Humans , Thrombopoiesis/genetics , Tubulin/metabolism , Tubulin/genetics , Methylation , Histone-Lysine N-Methyltransferase/genetics , Histone-Lysine N-Methyltransferase/metabolism , Mice, Inbred C57BL , Mice , Platelet Count
6.
Exp Eye Res ; 242: 109871, 2024 May.
Article in English | MEDLINE | ID: mdl-38527580

ABSTRACT

Myeloid derived suppressor cells (MDSCs) are a heterogenous population of immature hematopoietic precursors with known immunoregulatory functions. The immunosuppressive role of MDSCs has been highlighted in several inflammatory ophthalmic disorders; however, their therapeutic application in suppressing the immune-mediated changes in dry eye disease (DED) has not been studied. We observed significant reduction in antigen presenting cell (APC) frequencies and their maturation in the presence of MDSCs. Moreover, co-culturing MDSCs with T helper 17 cells (Th17) resulted in reduced Th17 frequencies and their IL-17 expression. On the contrary, MDSCs maintained regulatory T cell frequencies and enhanced their function in-vitro. Furthermore, we delineated the role of interleukin-10 (IL-10) secreted by MDSCs in their immunoregulatory functions. We confirmed these results by flow cytometry analysis and observed that treatment with MDSCs in DED mice effectively suppressed the maturation of APCs, pathogenic Th17 response, and maintained Treg function and significantly ameliorated the disease. The results in this study highlight the potential therapeutic application of MDSCs in treating refractory DED.


Subject(s)
Disease Models, Animal , Dry Eye Syndromes , Flow Cytometry , Mice, Inbred C57BL , Myeloid-Derived Suppressor Cells , T-Lymphocytes, Regulatory , Th17 Cells , Animals , Myeloid-Derived Suppressor Cells/immunology , Dry Eye Syndromes/immunology , Dry Eye Syndromes/metabolism , Mice , Th17 Cells/immunology , T-Lymphocytes, Regulatory/immunology , Antigen-Presenting Cells/immunology , Female , Disease Progression , Interleukin-10/metabolism , Cells, Cultured , Coculture Techniques
7.
Am J Transplant ; 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38514014

ABSTRACT

Highly inflamed and neovascularized corneal graft beds are known as high-risk (HR) environments for transplant survival. One of the primary factors leading to this rejection is reduction in the suppressive function of regulatory T cells (Treg). Our results show that myeloid-derived suppressor cells (MDSC) counteract interleukin-6-mediated Treg dysfunction by expressing interleukin-10. Additionally, MDSC maintain forkhead box P3 stability and their ability to suppress IFN-γ+ Th1 cells. Administering MDSC to HR corneal transplant recipients demonstrates prolonged graft survival via promotion of Treg while concurrently suppressing IFN-γ+ Th1 cells. Moreover, MDSC-mediated donor-specific immune tolerance leads to long-term corneal graft survival as evidenced by the higher survival rate or delayed survival of a second-party C57BL/7 (B6) graft compared to those of third-party C3H grafts observed in contralateral low-risk or HR corneal transplantation of BALB/c recipient mice, respectively. Our study provides compelling preliminary evidence demonstrating the effectiveness of MDSC in preventing Treg dysfunction, significantly improving graft survival in HR corneal transplantation, and showing promising potential for immune tolerance induction.

8.
Biomolecules ; 14(2)2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38397406

ABSTRACT

Alpha-melanocyte-stimulating hormone (α-MSH) and its binding receptors (the melanocortin receptors) play important roles in maintaining ocular tissue integrity and immune homeostasis. Particularly extensive studies have demonstrated the biological functions of α-MSH in both immunoregulation and cyto-protection. This review summarizes the current knowledge of both the physiological and pathological roles of α-MSH and its receptors in the eye. We focus on recent developments in the biology of α-MSH and the relevant clinical implications in treating ocular diseases.


Subject(s)
Melanocortins , alpha-MSH , Humans , alpha-MSH/pharmacology , alpha-MSH/metabolism , Receptors, Melanocortin/metabolism , Inflammation/drug therapy , Cell Death
9.
Cells ; 13(4)2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38391935

ABSTRACT

Macrophages play a crucial role in the innate immune response, serving as key effector cells in the defense against pathogens. Although the role of the large-conductance voltage and calcium-activated potassium channel, also known as the KCa1.1 or BK channel, in regulating neurotransmitter release and smooth muscle contraction is well known, its potential involvement in immune regulation remains unclear. We employed BK-knockout macrophages and noted that the absence of a BK channel promotes the polarization of macrophages towards a pro-inflammatory phenotype known as M1 macrophages. Specifically, the absence of the BK channel resulted in a significant increase in the secretion of the pro-inflammatory cytokine IL-6 and enhanced the activity of extracellular signal-regulated kinases 1 and 2 (Erk1/2 kinases), Ca2+/calmodulin-dependent protein kinase II (CaMKII), and the transcription factor ATF-1 within M1 macrophages. Additionally, the lack of the BK channel promoted the activation of the AIM2 inflammasome without affecting the activation of the NLRC4 and NLRP3 inflammasomes. To further investigate the role of the BK channel in regulating AIM2 inflammasome activation, we utilized BK channel inhibitors, such as paxilline and iberiotoxin, along with the BK channel activator NS-11021. Pharmacological inactivation of the BK channel increased, and its stimulation inhibited IL-1ß production following AIM2 inflammasome activation in wild-type macrophages. Moreover, wild-type macrophages displayed increased calcium influx when activated with the AIM2 inflammasome, whereas BK-knockout macrophages did not due to the impaired extracellular calcium influx upon activation. Furthermore, under conditions of a calcium-free medium, IL-1ß production following AIM2 inflammasome activation was increased in both wild-type and BK-knockout macrophages. This suggests that the BK channel is required for the influx of extracellular calcium in macrophages, thus limiting AIM2 inflammasome activation. In summary, our study reveals a regulatory role of the BK channel in macrophages under inflammatory conditions.


Subject(s)
Inflammasomes , Large-Conductance Calcium-Activated Potassium Channels , Inflammasomes/metabolism , Large-Conductance Calcium-Activated Potassium Channels/metabolism , Calcium/metabolism , Macrophages/metabolism , Immunity, Innate , Calcium-Calmodulin-Dependent Protein Kinases/metabolism
10.
Front Pharmacol ; 14: 1270787, 2023.
Article in English | MEDLINE | ID: mdl-38034997

ABSTRACT

Aims: Myocardial ischemia-reperfusion (I/R) injury markedly undermines the protective benefits of revascularization, contributing to ventricular dysfunction and mortality. Due to complex mechanisms, no efficient ways exist to prevent cardiomyocyte reperfusion damage. Vagus nerve stimulation (VNS) appears as a potential therapeutic intervention to alleviate myocardial I/R injury. Hence, this meta-analysis intends to elucidate the potential cellular and molecular mechanisms underpinning the beneficial impact of VNS, along with its prospective clinical implications. Methods and Results: A literature search of MEDLINE, PubMed, Embase, and Cochrane Database yielded 10 articles that satisfied the inclusion criteria. VNS was significantly correlated with a reduced infarct size following myocardial I/R injury [Weighed mean difference (WMD): 25.24, 95% confidence interval (CI): 32.24 to 18.23, p < 0.001] when compared to the control group. Despite high heterogeneity (I2 = 95.3%, p < 0.001), sensitivity and subgroup analyses corroborated the robust efficacy of VNS in limiting infarct expansion. Moreover, meta-regression failed to identify significant influences of pre-specified covariates (i.e., stimulation type or site, VNS duration, condition, and species) on the primary estimates. Notably, VNS considerably impeded ventricular remodeling and cardiac dysfunction, as evidenced by improved left ventricular ejection fraction (LVEF) (WMD: 10.12, 95% CI: 4.28; 15.97, p = 0.001) and end-diastolic pressure (EDP) (WMD: 5.79, 95% CI: 9.84; -1.74, p = 0.005) during the reperfusion phase. Conclusion: VNS offers a protective role against myocardial I/R injury and emerges as a promising therapeutic strategy for future clinical application.

11.
Exp Eye Res ; 236: 109657, 2023 11.
Article in English | MEDLINE | ID: mdl-37722586

ABSTRACT

Exposure to mustard agents, such as sulfur mustard (SM) and nitrogen mustard (NM), often results in ocular surface damage. This can lead to the emergence of various corneal disorders that are collectively referred to as mustard gas keratopathy (MGK). In this study, we aimed to develop a mouse model of MGK by using ocular NM exposure, and describe the subsequent structural changes analyzed across the different layers of the cornea. A 3 µL solution of 0.25 mg/mL or 5 mg/mL NM was applied to the center of the cornea via a 2-mm filter paper for 5 min. Mice were evaluated prior to and after exposure on days 1, 3, 7, 14, and 28 for 4 weeks using slit lamp examination with fluorescein staining. Anterior segment optical coherence tomography (AS-OCT) and in vivo confocal microscopy (IVCM) tracked changes in the epithelium, stroma, and endothelium of the cornea. Histologic evaluation was used to examine corneal cross-sections collected at the completion of follow-up. Following exposure, mice experienced central corneal epithelial erosion and thinning, accompanied by a decreased number of nerve branches in the subbasal plexus and increased activated keratocytes in the stroma in both dosages. The epithelium was recovered by day 3 in the low dose group, followed by exacerbated punctuate erosions alongside persistent corneal edema that arose and continued onward to four weeks post-exposure. The high dose group showed persistent epitheliopathy throughout the study. The endothelial cell density was reduced, more prominent in the high dose group, early after NM exposure, which persisted until the end of follow-up, along with increased polymegethism and pleomorphism. Microstructural changes in the central cornea at 4 weeks post-exposure included dysmorphic basal epithelial cells and reduced epithelial thickness, and in the limbal cornea included decreased cellular layers. We present a mouse model of MGK using NM that successfully replicates ocular injury caused by SM in humans who have been exposed to mustard gas.


Subject(s)
Corneal Diseases , Corneal Edema , Corneal Ulcer , Mustard Gas , Humans , Animals , Mice , Mustard Gas/toxicity , Mechlorethamine/toxicity , Cornea/pathology , Corneal Diseases/chemically induced , Corneal Diseases/pathology , Corneal Ulcer/pathology , Vision Disorders/pathology , Microscopy, Confocal
12.
J Med Internet Res ; 25: e46092, 2023 07 26.
Article in English | MEDLINE | ID: mdl-37494107

ABSTRACT

BACKGROUND: Telephone-assisted cardiopulmonary resuscitation (T-CPR) has proven to be a crucial intervention in enhancing the ability of lay responders to perform cardiopulmonary resuscitation (CPR) during telehealth emergency services. While the majority of established T-CPR protocols primarily focus on guiding individual rescuers, there is a lack of emphasis on instructing and coordinating multiple lay responders to perform resuscitation collaboratively. OBJECTIVE: This study aimed to develop an innovative team-based tele-instruction tool to efficiently organize and instruct multiple lay responders on the CPR process and to evaluate the effectiveness and feasibility of the tool. METHODS: We used a mixed methods design in this study. We conducted a randomized controlled simulation trial to conduct the quantitative analysis. The intervention groups used the team-based tele-instruction tool for team resuscitation, while the control groups did not have access to the tool. Baseline resuscitation was performed during the initial phase (phase I test). Subsequently, all teams watched a team-based CPR education training video and finished a 3-person practice session with teaching followed by a posttraining test (phase II test). In the qualitative analysis, we randomly selected an individual from each team and 4 experts in emergency medical services to conduct semistructured interviews. The purpose of these interviews was to evaluate the effectiveness and feasibility of this tool. RESULTS: The team-based tele-instruction tool significantly improved the quality of chest compression in both phase I and phase II tests. The average compression rates were more appropriate in the intervention groups compared to the control groups (median 104.5, IQR 98.8-111.8 min-1 vs median 112, IQR 106-120.8 min-1; P=.04 in phase I and median 117.5, IQR 112.3-125 min-1 vs median 111, IQR 105.3-119 min-1; P=.03 in phase II). In the intervention group, there was a delay in the emergency response time compared to that in the control group (time to first chest compression: median 20, IQR 15-24.8 seconds vs median 25, IQR 20.5-40.3 seconds; P=.03; time to open the airway: median 48, IQR 36.3-62 seconds vs median 73.5, IQR 54.5-227.8 seconds; P=.01). However, this delay was partially mitigated after the phase II test. The qualitative results confirmed the compatibility and generalizability of the team-based tele-instruction tool, demonstrating its ability to effectively guide multiple lay responders through teamwork and effective communication with telecommunicators. CONCLUSIONS: The use of the team-based tele-instruction tool offers an effective solution to enhance the quality of chest compression among multiple lay responders. This tool facilitated the organization of resuscitation teams by dispatchers and enabled efficient cooperation. Further assessment of the widespread adoption and practical application of the team-based tele-instruction tools in real-life rescue scenarios within the telehealth emergency services system is warranted.


Subject(s)
Cardiopulmonary Resuscitation , Emergency Medical Services , Telemedicine , Humans , Cardiopulmonary Resuscitation/education , Telephone
13.
Int J Cardiovasc Imaging ; 39(9): 1667-1675, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37233916

ABSTRACT

PURPOSE: In most clinical trials, intracardiac echocardiography (ICE) has provided fewer views than the four standard views provided by transesophageal echocardiography (TEE) when assessing left atrial appendage closure (LAAC) devices. This study aimed to determine if ICE guided by the CartoSound system achieve adequate high-quality views and similar clinical outcomes as TEE during LAAC. METHODS: This study prospectively enrolled 202 patients who underwent LAAC using either ICE (n = 69), TEE (n = 121), or a combination of ICE and TEE (n = 12) as the procedural imaging under local anesthesia. A novel multi-angled "FLAVOR" approach was used for assessment in the ICE group. RESULTS: ICE allowed visualization of the implanted devices in all patients at all proposed angles with long-axis views while two-dimensional (2D) TEE showed short-axis views in 1 or 2 angles in 24.2% of cases, which was more prevalent when the pulmonary ridge was covered by the occluder. In the combined ICE-TEE cohort, 2D-TEE failed to detect peri-device leak in 1 patient. The complication rates were similar between the ICE and TEE groups. Shorter fluoroscopy time, lower radiation dose and contrast usage were founded in the ICE group. At first TEE follow-up, the rate and degree of peri-device leak were similar between the ICE and TEE groups. CONCLUSION: A systematic ICE protocol using a CartoSound module to guide LAAC was reliable for comprehensive long-axis imaging assessment compared with 2D/3D TEE under local anesthesia with a shorter fluoroscopy time, lower radiation dose, and less use of contrast.


Subject(s)
Atrial Appendage , Atrial Fibrillation , Humans , Echocardiography, Transesophageal , Atrial Appendage/diagnostic imaging , Treatment Outcome , Atrial Fibrillation/diagnostic imaging , Atrial Fibrillation/surgery , Cardiac Catheterization , Predictive Value of Tests , Echocardiography/methods
14.
Am J Transplant ; 23(9): 1345-1358, 2023 09.
Article in English | MEDLINE | ID: mdl-37245642

ABSTRACT

Corneal transplantation is the most common form of solid tissue grafting, with an approximately 80% to 90% success rate. However, success rates may decline when donor tissues are derived from patients with a history of diabetes mellitus (DM). To evaluate the underlying immunopathologic processes that cause graft rejection, we used streptozotocin-induced type 1 DM (DM1) and transgenic Lepob/ob type 2 DM (DM2) diabetic murine models as donors and nondiabetic BALB/c as recipients. DM resulted in an increased frequency of corneal antigen-presenting cells (APCs) with an acquired immunostimulatory phenotype. Following transplantation, recipients that received either type of diabetic graft showed increased APC migration and T helper type 1 alloreactive cells, impaired functional regulatory T cells, and graft survival. Insulin treatment in streptozotocin-induced diabetic mice led to an increased tolerogenic profile of graft APC, lower T helper type 1 sensitization, and a higher frequency of functional regulatory T cells with high suppressive capacity, reflected in increased graft survival. We conclude that both DM1 and DM2 in donors can impact corneal APC functional phenotype, rendering the tissue more immunogenic and thereby increasing the risk of graft failure.


Subject(s)
Corneal Transplantation , Diabetes Mellitus, Experimental , Animals , Mice , Diabetes Mellitus, Experimental/surgery , Diabetes Mellitus, Experimental/pathology , Streptozocin , Cornea , Antigen-Presenting Cells
15.
Exp Eye Res ; : 109495, 2023 May 02.
Article in English | MEDLINE | ID: mdl-37142048

ABSTRACT

Exposure to mustard agents, such as sulfur mustard (SM) and nitrogen mustard (NM), often results in ocular surface damage. This can lead to the emergence of various corneal disorders that are collectively referred to as mustard gas keratopathy (MGK). In this study, we aimed to develop a mouse model of MGK by using ocular NM exposure, and describe the subsequent structural changes analyzed across the different layers of the cornea. A 3 µL solution of 0.25 mg/mL NM was applied to the center of the cornea via a 2-mm filter paper for 5 min. Mice were evaluated prior to and after exposure on days 1 and 3, and weekly for 4 weeks using slit lamp examination with fluorescein staining. Anterior segment optical coherence tomography (AS-OCT) and in vivo confocal microscopy (IVCM) tracked changes in the epithelium, stroma, and endothelium of the cornea. Histologic evaluation and immunostaining were used to examine corneal cross-sections collected at the completion of follow-up. A biphasic ocular injury was observed in mice exposed to NM, most prominent in the corneal epithelium and anterior stroma. Following exposure, mice experienced central corneal epithelial erosions and thinning, accompanied by a decreased number of nerve branches in the subbasal plexus and increased activated keratocytes in the stroma. The epithelium was recovered by day 3, followed by exacerbated punctuate erosions alongside persistent stromal edema that arose and continued onward to four weeks post-exposure. The endothelial cell density was reduced on the first day after NM exposure, which persisted until the end of follow-up, along with increased polymegethism and pleomorphism. Microstructural changes in the central cornea at this time included dysmorphic basal epithelial cells, and in the limbal cornea included decreased cellular layers and p63+ area, along with increased DNA oxidization. We present a mouse model of MGK using NM that successfully replicates ocular injury caused by SM in humans who have been exposed to mustard gas. Our research suggests DNA oxidation contributes to the long-term effects of nitrogen mustard on limbal stem cells.

16.
FASEB J ; 37(4): e22855, 2023 04.
Article in English | MEDLINE | ID: mdl-36906286

ABSTRACT

Chronic uveitis comprises heterogeneous clinical entities characterized by sustained and recurrent intraocular inflammation that is believed to be driven by autoimmune responses. The management of chronic uveitis is challenging with the limited availability of efficacious treatments, and the underlying mechanisms mediating disease chronicity remain poorly understood as the majority of experimental data are derived from the acute phase of the disease (the first 2-3 weeks post-induction). Herein, we investigated the key cellular mechanisms underlying chronic intraocular inflammation using our recently established murine model of chronic autoimmune uveitis. We demonstrate unique long-lived CD44hi IL-7R+ IL-15R+ CD4+ memory T cells in both retina and secondary lymphoid organs after 3 months postinduction of autoimmune uveitis. These memory T cells functionally exhibit antigen-specific proliferation and activation in response to retinal peptide stimulation in vitro. Critically, these effector-memory T cells are capable of effectively trafficking to the retina and accumulating in the local tissues secreting both IL-17 and IFN-γ upon adoptively transferred, leading to retinal structural and functional damage. Thus, our data reveal the critical uveitogenic functions of memory CD4+ T cells in sustaining chronic intraocular inflammation, suggesting that memory T cells can be a novel and promising therapeutic target for treating chronic uveitis in future translational studies.


Subject(s)
Autoimmune Diseases , Retinal Diseases , Uveitis , Mice , Humans , Animals , Disease Models, Animal , CD4-Positive T-Lymphocytes , Inflammation
17.
J Clin Med ; 12(3)2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36769499

ABSTRACT

The optimal antithrombotic strategy after percutaneous left atrial appendage closure (LAAC) has not yet been established. The advisability of administering low-dose direct oral anticoagulation after LAAC to patients at high risk of bleeding is uncertain. Thus, in the present study, we evaluated the safety and effectiveness of reduced-(15 mg) or half-dose rivaroxaban (10 mg) versus warfarin regarding real-world risks of thromboembolism, bleeding, and device-related thrombosis (DRT) after LAAC. Patients with non-valvular atrial fibrillation and HASBLED ≥ 3 who had undergone successful LAAC device implantation from October 2014 to April 2020 were screened and those who had received 10 mg or 15 mg rivaroxaban or warfarin therapy were enrolled. The patients were followed up 45 days and 6 months after LAAC to evaluate outcomes, including death, thromboembolism, major bleeding, and DRT. Of 457 patients with HASBLED ≥ 3 who had undergone LAAC, 115 had received warfarin and 342 rivaroxaban (15 mg: N = 164; 10 mg: N = 178). There were no significant differences in the incidence of thromboembolism or DRT between the warfarin and both doses of rivaroxaban groups (all p > 0.05). The incidence of major bleeding was significantly higher in the warfarin group than in either the reduced- or half-dose rivaroxaban groups (warfarin vs. rivaroxaban 15 mg: 2.6% vs. 0%, p = 0.030; warfarin vs. rivaroxaban 10 mg: 2.6% vs. 0%, p = 0.038). Either reduced- or half-dose rivaroxaban may be an effective and safe alternative to warfarin therapy in patients with LAAC and who are at high risk of bleeding, the risk of thromboembolism being similar and of major bleeding lower for both doses of rivaroxaban.

18.
Mucosal Immunol ; 16(5): 711-726, 2023 Oct.
Article in English | MEDLINE | ID: mdl-36642378

ABSTRACT

Corneal transplant rejection primarily occurs because of the T helper 1 (Th1) effector cell-mediated immune response of the host towards allogeneic tissue. The evidence suggests that type 1 migratory conventional CD103+ dendritic cells (CD103+DC1) acquire an immunosuppressive phenotype in the tumor environment; however, the involvement of CD103+DC1 in allograft survival continues to be an elusive question of great clinical significance in tissue transplantation. In this study, we assess the role of CD103+DC1 in suppressing Th1 alloreactivity against transplanted corneal allografts. The immunosuppressive function of CD103+DC1 has been extensively studied in non-transplantation settings. We found that host CD103+DC1 infiltrates the corneal graft and migrates to the draining lymph nodes to suppress alloreactive CD4+ Th1 cells via the programmed death-ligand 1 axis. The systemic depletion of CD103+ DC1 in allograft recipients leads to amplified Th1 activation, impaired Treg function, and increased rate of allograft rejection. Although allograft recipient Rag1 null mice reconstituted with naïve CD4+CD25- T cells efficiently generated peripheral Treg cells (pTreg), the CD103+DC1-depleted mice failed to generate pTreg. Furthermore, adoptive transfer of pTreg failed to rescue allografts in CD103+DC1-depleted recipients from rejection. These data demonstrate the critical role of CD103+DC1 in regulating host alloimmune responses.

19.
Transplantation ; 107(6): 1302-1310, 2023 06 01.
Article in English | MEDLINE | ID: mdl-36584368

ABSTRACT

BACKGROUND: Corneal transplantation outcomes are generally less favorable in young children compared with adults. The purpose of this study was to determine the immunological mechanisms underlying this difference. METHODS: A murine model of allogeneic corneal transplantation was used in the study, and graft survival was determined by evaluating opacity scores for 8 wk. Syngeneic transplantation in the very young host served as a surgical control. The frequencies of total and activated natural killer (NK) cells in cornea posttransplantation were kinetically evaluated using flow cytometry. The regulatory T cell (Treg) frequency and function in naive animals were assessed by flow cytometry and in vitro suppression assays, respectively. Finally, graft survival and immune responses were determined in NK cell-depleted, or adult naive Treg-transferred, young hosts. RESULTS: Corneal allograft survival in the very young recipients was significantly lower than in adult hosts. The frequencies of total NK cells and their interferon gamma-expressing subset in the cornea were significantly higher in the very young mice posttransplantation. In ungrafted mice, frequencies of Treg in draining lymph nodes as well as their capabilities to suppress NK-cell secretion of interferon gamma were lower in the very young compared with adults. In NK cell-depleted or adult Treg--transferred very young recipients, the allograft survival was significantly improved along with the suppressed NK-cell response. CONCLUSIONS: Our data demonstrate that amplified activity of NK cells, together with lower suppressive function of Treg, contributes to early rejection of corneal allografts in very young graft recipients.


Subject(s)
Corneal Transplantation , T-Lymphocytes, Regulatory , Mice , Animals , Interferon-gamma , Cornea , Killer Cells, Natural , Graft Rejection , Mice, Inbred C57BL , Mice, Inbred BALB C
20.
Gene ; 851: 147010, 2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36349576

ABSTRACT

Copy number variation (CNV), as one of the important variations in the biological genome, refers to the deletion and duplication of genomic segments between 1 kb and 50 kb caused by genomic rearrangements. Currently, many copy number variations have been found to be significantly associated with important economic traits such as growth, development and reproduction of cattle. However, the study of MUC19 gene has not been reported. In this study, we detected an appropriate correlation between MUC19 gene and growth traits of Chinese cattle. We detected the distribution of MUC19-CNV across Qinchuan cattle (QC), Pinan cattle (PN), Xianan cattle (XN), Yunling cattle (YL), Guyuan cattle (GY), Jiaxian cattle (JX), and analyzed the association between types of MUC19-CNV and growth traits through SPSS20.0 software and method of ANOVA. The results showed that various types of CNV were present in each breed of cattle, but there were discrepancies in the distribution of copy number variant types. The Association analysis result showed that CNV of MUC19 gene showed a postive effect in cattle growth traits: the copy number of MUC19 was significantly correlated with hip width of PN cattle (P < 0.01), height at hip cross and withers height of PN cattle (P < 0.05), hip width and body length of JX cattle (P < 0.05), Huckle bone width of YL cattle (P < 0.05).


Subject(s)
DNA Copy Number Variations , Polymorphism, Single Nucleotide , Cattle/genetics , Animals , DNA Copy Number Variations/genetics , Phenotype , Genome , China
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