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Introduction: Theory of mind (ToM) refers to the ability to understand and attribute mental states to oneself and others. A ToM measure is warranted for preschool children to assess their ToM development from a multidimensional perspective (i.e., cognitive and affective dimensions). This study aimed to develop the Preschool Theory of Mind Assessment (ToMA-P) and to evaluate its construct validity and applicability. Methods: The ToMA-P was developed based on comprehensive literature review and revised with expert panel feedback. Its psychometric properties were evaluated in 205 typically developing preschoolers with Rasch analysis for its dimensionality, item difficulties, and convergent validity. Results: The results indicated that all ToMA-P items, except for one, fit the hypothesized two-dimensional construct. The item difficulties in the cognitive and affective dimensions followed developmental sequences. The ToMA-P scores exhibited good convergent validity, as evidenced by its significant correlations with age, verbal comprehension, adaptive functions, and daily ToM performance (p < 0.05). Children's responses and behaviors also showed that the ToMA-P has good applicability. Discussion: This study provides empirical evidence that the ToMA-P measures cognitive and affective ToM following developmental sequences, and that it has potential as a clinical tool for assessing ToM in preschool children.
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Effective identification of T1a stage cancer is crucial for planning endoscopic resection for early gastric cancers. The present study aimed to determine the diagnostic value of the double-track sign in patients with T1a gastric cancer using computed tomography (CT) imaging. A total of 152 patients diagnosed with pathologically proven T1a gastric cancer at The First Affiliated Hospital of Zhengzhou University (Zhengzhou, China) between July 2011 and August 2021 were retrospectively reviewed. The control group consisted of 2,926 patients with gastritis. Clinical data, including patient characteristics and preoperative CT imaging findings with gastric morphological features, were reviewed and analyzed. Out of 51 patients with T1a gastric cancer finally included, 31 (60.8%) exhibited local double-track enhancement changes of the stomach, referred to as the 'double-track sign', on CT images. In addition, four patients (7.8%) had well-enhanced mucosal thickening of the gastric wall. Of the 2,926 control subjects, none had any double-track sign and six patients (0.2%) had local gastric wall thickening with abnormally strengthened enhancement. In conclusion, a double-track sign on CT images is beneficial in the diagnostic differentiation of T1a gastric cancer.
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The aim of this study was to explore the effects of Huangqin Tang(HQT) on the NLRP3/Caspase-1 signaling pathway in mice with DSS-induced ulcerative colitis(UC). C57BL/6J mice were randomly divided into a blank group, a model group(DSS group), and low-, medium-and high-dose HQT groups(HQT-L, HQT-M, and HQT-H), and western medicine mesalazine group(western medicine group). The UC model was induced in mice. Subsequently, the mice in the HQT-L, HQT-M, HQT-H groups, and the western medicine group were given low-, medium-, high-dose HQT, and mesalazine suspension by gavage, respectively, while those in the blank and DSS groups were given an equal volume of distilled water by gavage. After 10 days of administration, the body weight, DAI scores, and colonic histopathological score of mice in each group were determined. The levels of IL-6, IL-10, IL-1ß, and TNF-α in serum were determined by ELISA. The mRNA expression of NLRP3 and Caspase-1 in colon tissues was determined by RT-qPCR. The protein expression of NLRP3 and Caspase-1 in colon tissues was detected by immunohistochemistry. The results showed that compared with the blank group, the DSS group showed decreased body weight of mice and increased DAI scores and intestinal histopathological score. Compared with the DSS group, the HQT groups and the western medicine group showed improved DAI scores, especially in the HQT-M, HQT-H, and the western medicine groups(P<0.05). The intestinal histopathological scores of the HQT groups and the western medicine group significantly decreased, especially in the HQT-M, HQT-H, and the western medicine groups(P<0.05). In addition, compared with the blank group, the DSS group showed elevated expression of NLRP3 and Caspase-1 in colon tissues, increased serum levels of IL-6, IL-1ß, and TNF-α, and decreased IL-10 level. Compared with the DSS group, the HQT groups and the western medicine group displayed decreased expression of NLRP3 and Caspase-1 in colon tissues, reduced serum levels of IL-6, IL-1ß, and TNF-α, and increased IL-10 level. The improvement was the most significant in the HQT-H group and the western medicine group(P<0.01). In conclusion, HQT may reduce the expression of NLRP3 and Caspase-1 in colon tissues, reduce the se-rum levels of IL-6, IL-1ß, and TNF-α, and increase the expression of IL-10 by regulating the classic pyroptosis pathway of NLRP3/Caspase-1, thereby improving the symptoms of intestinal injury and inflammatory infiltration of intestinal mucosa in DSS mice to achieve its therapeutic effect.
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Colite Ulcerativa , Medicamentos de Ervas Chinesas , Animais , Camundongos , Caspase 1/genética , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/genética , Colo , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Interleucina-10/genética , Interleucina-6/genética , Mesalamina/farmacologia , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Scutellaria baicalensis/química , Fator de Necrose Tumoral alfa/metabolismo , Medicamentos de Ervas Chinesas/farmacologiaRESUMO
The Theory of Mind Inventory-2 (ToMI-2) is a promising measure for assessing theory of mind (ToM) and social-related functions. However, limited evidence on its factorial validity hampers score interpretation. To examine the factorial validity, confirmatory factor analysis for two currently-available structures was performed in 420 typically developing children aged three to seven years. One, the development-based structure, contains three stages of ToM development: the early, basic, and advanced ToM stages. The other, the social-related structure, comprises three social-related ToM functions: emotion recognition, mental state term comprehension, and pragmatics. The results showed that these structures and the unidimensionality of each domain were not supported even after modifications. Thus, further revisions and examinations of the underlying structures of the ToMI-2 are needed.
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Transtorno do Espectro Autista , Teoria da Mente , Criança , Humanos , Desenvolvimento Infantil , Compreensão , EmoçõesRESUMO
BACKGROUND: There is a lack of robust prognostic markers for upper gastrointestinal (GI) tract cancers, including esophageal, gastric, and esophagogastric junction cancers. T cell immunoglobulin and mucin-domain containing-3 (TIM3) plays a key immunomodulatory role and is linked to the prognosis of various cancers. However, the significance of TIM3 in upper GI tract tumors is still uncertain. AIM: To investigate the prognostic value of TIM3 expression in upper GI tract tumors. METHODS: A literature search was conducted on the PubMed, Embase, and Web of Science databases for relevant studies published until June 2023. After screening and quality assessment, studies that met the criteria were included in the meta-analysis. Statistical methods were used for the pooled analysis to assess the association of TIM3 expression in upper GI tract tumors with the prognosis and clinicopathological parameters. The results were reported with the hazard ratio (HR) and 95% confidence interval (CI). RESULTS: Nine studies involving 2556 patients with upper GI tract cancer were included. High TIM3 expression was associated with a worse prognosis in upper GI tract cancer (HR: 1.17, 95%CI: 1.01-1.36). Positive expression of TIM3 in gastric cancer was correlated with the T and N stage, but the difference was not statistically significant. However, TIM3 overexpression was significantly correlated with the TNM stage (odds ratio: 1.21, 95%CI: 0.63-2.33; P < 0.05). TIM3 expression showed no association with the other clinicopathological parameters. CONCLUSION: High expression of TIM3 in the upper GI tract cancer is associated with a worse prognosis and advanced T or N stages, indicating its potential value as a prognostic biomarker. These findings may provide a basis for the personalized treatment of upper GI tract cancers.
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Progressive ischemic stroke (PIS) is featured by progressive neurological dysfunction after ischemia. Ischemia-evoked neuroinflammation is implicated in the progressive brain injury after cerebral ischemia, while Caspase-1, an active component of inflammasome, exaggerates ischemic brain injury. Current Caspase-1 inhibitors are inadequate in safety and druggability. Here, we investigated the efficacy of CZL80, a novel Caspase-1 inhibitor, in mice with PIS. Mice and Caspase-1-/- mice were subjected to photothrombotic (PT)-induced cerebral ischemia. CZL80 (10, 30 mg·kg-1·d-1, i.p.) was administered for one week after PT onset. The transient and the progressive neurological dysfunction (as foot faults in the grid-walking task and forelimb symmetry in the cylinder task) was assessed on Day1 and Day4-7, respectively, after PT onset. Treatment with CZL80 (30 mg/kg) during Day1-7 significantly reduced the progressive, but not the transient neurological dysfunction. Furthermore, we showed that CZL80 administered on Day4-7, when the progressive neurological dysfunction occurred, produced significant beneficial effects against PIS, suggesting an extended therapeutic time-window. CZL80 administration could improve the neurological function even as late as Day43 after PT. In Caspase-1-/- mice with PIS, the beneficial effects of CZL80 were abolished. We found that Caspase-1 was upregulated during Day4-7 after PT and predominantly located in activated microglia, which was coincided with the progressive neurological deficits, and attenuated by CZL80. We showed that CZL80 administration did not reduce the infarct volume, but significantly suppressed microglia activation in the peri-infarct cortex, suggesting the involvement of microglial inflammasome in the pathology of PIS. Taken together, this study demonstrates that Caspase-1 is required for the progressive neurological dysfunction in PIS. CZL80 is a promising drug to promote the neurological recovery in PIS by inhibiting Caspase-1 within a long therapeutic time-window.
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Lesões Encefálicas , Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Camundongos , Animais , Inflamassomos , Modelos Animais de Doenças , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Microglia , Infarto Cerebral , Caspase 1 , Lesões Encefálicas/patologia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/patologia , Camundongos Endogâmicos C57BLRESUMO
PURPOSE: It has been established that obstructive sleep apnea (OSA) is an independent risk factor for atherosclerosis. Chronic intermittent hypoxia (CIH) activates sympathoadrenal system and upregulates ß3 adrenergic receptor (ß3 AR). However, the effect of selective ß3 AR agonist mirabegron in CIH-induced atherosclerosis remains unknown. METHODS: We generated a CIH-induced atherosclerosis model through exposing ApoE-/- mice to CIH (8 h per day, cyclic inspiratory oxygen fraction 5-21%, 60-s cycle) for 6 weeks after 4-week high-fat dieting and investigated the effects of mirabegron, a selective ß3 AR agonist, on CIH-induced atherosclerosis. The coronary endarterectomy (CE) specimens from coronary artery disease patients with OSA and without OSA were collected. RESULTS: The expression of ß3 AR was significantly elevated in CIH-induced atherosclerosis model. Furthermore, treatment with mirabegron (10mg/kg per day by oral administration for 6 weeks) ameliorated atherosclerosis in ApoE-/- mice in CIH but not in normoxia. Mechanistically, mirabegron activated ß3 AR and ameliorated intraplaque oxidative stress by suppressing p22phox expression and reactive oxygen species (ROS) level. In addition, in human CE specimens, ß3 AR was also upregulated associated with increased p22phox expression and ROS level both in the lumen and in the plaque of coronary artery in OSA subjects. CONCLUSION: This study first demonstrated that mirabegron impeded the progression of CIH-induced atherosclerosis, at least in part, via ß3 AR-mediated oxidative stress, suggesting a promising therapeutic strategy for protecting against atherosclerosis induced by CIH.
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Aterosclerose , Apneia Obstrutiva do Sono , Acetanilidas , Animais , Apolipoproteínas E , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Aterosclerose/prevenção & controle , Modelos Animais de Doenças , Humanos , Hipóxia , Camundongos , Oxigênio , Espécies Reativas de Oxigênio/metabolismo , Receptores Adrenérgicos , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/tratamento farmacológico , TiazóisRESUMO
INTRODUCTION: Baricitinib is an oral, selective inhibitor of Janus kinase which demonstrates clinical efficacy in patients with rheumatoid arthritis (RA). This report aims to analyze the onset time of baricitinib in Chinese patients with moderately to severely active RA who had an inadequate response to methotrexate. METHODS: This post hoc analysis evaluated clinical improvements of Chinese patients treated with baricitinib 4 mg once daily compared with placebo, based on data from a phase 3 study RA-BALANCE. Efficacy measures including American College of Rheumatology 20% (ACR20) response, ACR core set values, Disease Activity Score modified to include the 28 diarthrodial joint count (DAS28) using high-sensitivity C-reactive protein (hsCRP), DAS28-erythrocyte sedimentation rate, Simplified Disease Activity Index, Clinical Disease Activity Index, DAS28-hsCRP ≤ 3.2 response (low disease activity), and Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) were evaluated at weeks 1, 2, 4, 8, 12, 14, 16, 20, and 24 (except for FACIT-F evaluated every 4 weeks). A logistic regression model and an analysis of covariance model were used to analyze treatment comparisons of categorical and continuous measures, respectively. RESULTS: Statistically significant (p ≤ 0.05) improvements were observed as early as week 1 or 2 for the baricitinib group compared to placebo in almost all main efficacy measures. For other outcomes including 66 swollen joint count, 68 tender joint count, FACIT-F, and DAS28-hsCRP ≤ 3.2 response rate, differences were evident (p ≤ 0.05) by week 4 in the baricitinib group compared with placebo. Significant improvements in all efficacy measures were sustained through 24 weeks. CONCLUSIONS: Baricitinib demonstrated a rapid onset of efficacy on ACR20 response, ACR core set values, disease activity, and patient-reported outcome improvements in Chinese patients from RA-BALANCE. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT02265705.
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Antirreumáticos , Artrite Reumatoide , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Azetidinas , China , Método Duplo-Cego , Quimioterapia Combinada , Humanos , Metotrexato/uso terapêutico , Purinas , Pirazóis , Índice de Gravidade de Doença , Sulfonamidas , Resultado do TratamentoRESUMO
Contrast-induced encephalopathy (CIE) is a rare complication following percutaneous carotid and coronary interventions, and important diagnostic radiological signs include brain edema and cortical enhancement. In this report, we detail a case of probable CIE in an 84-year-old woman following a normal diagnostic coronary angiography (CAG) that involved 20 mL of the low-osmolar, non-ionic monomeric, iodine-based contrast agent iopromide (Ultravist 370). The patient was unconscious and presented with hemiparesis, hemianopia, recurrent seizures, and cardiac and respiratory arrest within minutes to hours following the procedure. Non-contrast computed tomography (CT) of the head showed increased subarachnoid density, cortical enhancement, and brain edema in the right hemisphere. Three days of rehydration, reduction in cranial pressure, and treatment with an anticonvulsant and dexamethasone resulted in a gradual recovery with no neurological deficits. This case highlights that severe neurotoxic symptoms may occur in response to low doses of low-osmolar, non-ionic, monomeric contrast agents. This finding is of importance to interventional cardiologists for diagnostic considerations and development of treatment plans.
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Encefalopatias/induzido quimicamente , Meios de Contraste/efeitos adversos , Angiografia Coronária/efeitos adversos , Iohexol/análogos & derivados , Idoso de 80 Anos ou mais , Encefalopatias/diagnóstico , Encefalopatias/terapia , Artérias Carótidas/efeitos dos fármacos , Meios de Contraste/administração & dosagem , Feminino , Humanos , Iodo/efeitos adversos , Iohexol/administração & dosagem , Iohexol/efeitos adversos , Resultado do TratamentoRESUMO
Melatonin receptors (MTs) are potential drug targets for stroke therapy. Ramelteon is a selective melatonin receptor agonist used to treat insomnia. In this study we investigated whether ramelteon could attenuate cerebral ischemia in mice. Acute focal cerebral ischemia was induced in mice via middle cerebral artery occlusion (MCAO). We found oral administration of ramelteon (3.0 mg/kg) significantly attenuated ischemic injury even when it was given 4 h after the onset of ischemia. We showed that administration of ramelteon (3.0 mg/kg) displayed comparable protective efficacy and length of effective time window as administration of edaravone (10 mg/kg, i.p.), which was used in clinic to treat ischemic stroke. Chronic ischemic brain injury was induced in mice using photothrombosis. Oral administration of ramelteon (3.0 mg · kg-1 · d-1) for 7 days after ischemia significantly attenuated functional deficits for at least 15 days. The neuroprotection of ramelteon was blocked by 4-P-PDOT, a specific MT antagonist. We further revealed that ramelteon significantly inhibited autophagy in the peri-infarct cortex in both the mouse ischemia models via regulating AMPK/mTOR signaling pathway. Intracerebroventricular injection of rapamycin, an autophagy activator, compromised the neuroprotection of ramelteon, suggesting ramelteon might attenuate ischemic injury by counteracting autophagic cell death. These data demonstrate for the first time the potential benefits of ramelteon in the treatment of both acute and chronic ischemic brain injury and provide the rationale for the application of ramelteon in stroke therapy.
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Lesão Encefálica Crônica/tratamento farmacológico , Indenos/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Receptores de Melatonina/agonistas , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Autofagia/efeitos dos fármacos , Encéfalo/patologia , Lesão Encefálica Crônica/patologia , Edaravone/uso terapêutico , Infarto da Artéria Cerebral Média/patologia , Camundongos , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismoRESUMO
AIM: Mitochondrial autophagy (mitophagy) clears damaged mitochondria and attenuates ischemic neuronal injury. Urolithin A (Uro-A) activates mitophagy in mammal cells and Caenorhabditis elegans. We explored neuroprotection of Uro-A against ischemic neuronal injury. METHODS: Mice were subjected to middle cerebral artery occlusion. The brain infarct and neurological deficit scores were measured. The N2a cells and primary cultured mice cortical neurons were subjected to oxygen-glucose deprivation and reperfusion (OGD/R). Uro-A was incubated during OGD/R, and cell injury was determined by MTT and LDH. Autophagosomes were visualized by transfecting mCherry-microtubule-associated protein 1 light chain 3 (LC3). The protein levels of LC3-II, p62, Translocase Of Inner Mitochondrial Membrane 23 (TIMM23), and cytochrome c oxidase subunit 4 isoform 1 (COX4I1) were detected by Western blot. The ER stress markers, activating transcription factor 6 (ATF6) and C/EBP homologous protein (CHOP), were determined by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Urolithin A alleviated OGD/R-induced injury in N2a cells and neurons and reduced ischemic brain injury in mice. Uro-A reinforced ischemia-induced autophagy. Furthermore, Uro-A-conferred protection was abolished by 3-methyladenine, suggesting the requirement of autophagy for neuroprotection. However, mitophagy was not further activated by Uro-A. Instead, Uro-A attenuated OGD/R-induced ER stress, which was abolished by 3-methyladenosine. Additionally, neuroprotection was reversed by ER stress inducer. CONCLUSION: Urolithin A protected against ischemic neuronal injury by reinforcing autophagy rather than mitophagy. Autophagy activation by Uro-A attenuated ischemic neuronal death by suppressing ER stress.
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Autofagia/efeitos dos fármacos , Isquemia Encefálica/prevenção & controle , Cumarínicos/uso terapêutico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Animais , Autofagia/fisiologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Cumarínicos/farmacologia , Estresse do Retículo Endoplasmático/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitofagia/fisiologia , Fármacos Neuroprotetores/farmacologiaRESUMO
To estimate the mortality and describe the causes of death in a large multicenter cohort of hospitalized patients with SLE in China. This was a retrospective study of a nationwide SLE cohort (10 centers, 29,510 hospitalized patients) from 2005 to 2014 in China. Standardized mortality ratios (SMRs) were calculated for all death and were stratified by sex and age. Chi-square test was used to determine whether the major causes of death vary in age, sex, duration of SLE, disease activity, or medications. Comparison between dead patients and survival controls was used to identify the risk factors for mortality. Logistic regression analysis was used to evaluate the risk factors for mortality. A total of 360 patients died during the study period, accounting for 1.22%. The overall SMR was 2.13 (95% CI 1.96, 2.30), with a particularly high SMR seen in subgroups characterized by younger age. Infection (65.8%) was the most common cause of death, followed by lupus nephritis (48.6%), hematological abnormality (18.1%), neuropsychiatric lupus/NPSLE (15.8%), and interstitial pneumonia (13.1%). Cardiovascular disease and malignancy contributed little to the causes of death. Infection, in particular severe pulmonary infection, emerged as the foremost risk factor for mortality, followed by lupus encephalopathy. However, lupus nephritis and hematological abnormalities occurred more frequently in survival patients. SLE patients at a younger age of diagnosis have a poorer prognosis. Infection dominated the causes of death in recent China. Ethnicity and medications might account for the differences in causes of death compared with western populations.
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Causas de Morte , Lúpus Eritematoso Sistêmico/mortalidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/complicações , Criança , China/epidemiologia , Feminino , Humanos , Infecções/complicações , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Adulto JovemRESUMO
The present paper reports a novel method for the determination of silicon content in straw fibrous material black liquor based on alpha-Si--Mo heteropoly acid spectrophotometry. The selected conditions were as follows: detection wavelength 360 nm, pH 4.0, and reaction time 10 min. It was found that the acidic soluble lignin in the sample liquor was the major interference species in the silicon content determination. The interference of acidic soluble lignin can be eliminated by hydrogen peroxide-nitric acid digestion method. The present method is not only simple, rapid, stable and less interferential, but also of good measurement precision and accuracy, with the relative standard deviations of 0.9%, and recoveries of 99.0%-102%. It is suitable for use in high silicon content of black liquor routine rapid analyses.
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We previously discovered a hamster monoclonal antibody, TAB4, against mouse PSGL-1/CD162 that can induce death of activated T cells. Here, we further investigated the potential of TAB4 in treating two murine models of T cell-mediated diseases. The results showed that administration of TAB4 suppressed incidence and severity of both GVHD and type I diabetes. Analyses of apoptotic T cells ex vivo shortly after antibody injection revealed a higher percentage of apoptosis among activated T cells in the TAB4-treated group than in the control group. Furthermore, restoration of functional donor T cells was observed in TAB4-treated mice. As TAB4 does not affect the binding of P-selectin to activated T cells, our data suggest that its long-lasting therapeutic effect on inhibiting disease progression is attained by specifically inducing apoptosis of activated T cells. These data hence extend our previous finding of the novel property of PSGL-1 and strongly indicate that the PSGL-1-specific apoptosis-inducing antibody is a new therapeutic agent possessing a great potential for controlling GVHD and other T cell-mediated autoimmune diseases.
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Anticorpos Monoclonais/biossíntese , Apoptose/imunologia , Diabetes Mellitus Tipo 1/terapia , Doença Enxerto-Hospedeiro/terapia , Glicoproteínas de Membrana/imunologia , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais/uso terapêutico , Sítios de Ligação de Anticorpos , Ligação Competitiva/imunologia , Cricetinae , Citocinas/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Modelos Animais de Doenças , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Ligantes , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos NOD , Selectina-P/metabolismo , Linfócitos T/metabolismoRESUMO
Increasing evidence has shown that death signaling in T cells is regulated in a complicated way. Molecules other than death receptors can also trigger T-cell death. Here, we demonstrate for the first time that P-selectin glycoprotein ligand-1 (PSGL-1) or CD162 molecules cross-linked by an anti-PSGL-1 monoclonal antibody, TAB4, can trigger a death signal in activated T cells. In contrast to classic cell death, PSGL-1-mediated T-cell death is caspase independent. It involves translocation of apoptosis-inducing factor from mitochondria to nucleus and mitochondrial cytochrome c release. Ultrastructurally, both peripheral condensation of chromatin and apoptotic body were observed in PSGL-1-mediated T-cell death. Collectively, this study demonstrates a novel role for PSGL-1 in controlling activated T-cell death and, thus, advances our understanding of immune regulation.