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1.
Artigo em Inglês | MEDLINE | ID: mdl-36768042

RESUMO

When considering how to improve public literacy and behavior related to specific themes, top priority is usually given to strategies that enhance relevant knowledge. Fostering attitude comes later. Understanding the mechanisms of behavior may help us develop better policy and educational strategies. However, how knowledge and attitude impact behavior is still under investigation. The aim of this study is to explore the relationships among ocean knowledge, attitude toward the ocean, and the intention to behave responsibly in the marine setting. Specifically, we investigated a potential mediation mechanism by recruiting a total of 266 participants, whose ocean knowledge, attitudes toward the ocean, and intention to behave responsibly were evaluated using questionnaires. The results indicate that a person's attitude toward the ocean may indeed be a mediating factor between ocean knowledge and their intention to show positive marine behavior. In order to engage people in responsible ocean behavior, other forms of assistance from marine policy and education are recommended. Additionally, it would be of interest for future studies to investigate the effects of attitude and attitude-related knowledge in the development of ocean actions.


Assuntos
Atitude , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Intenção , Inquéritos e Questionários , Escolaridade , Oceanos e Mares
2.
Rheumatology (Oxford) ; 62(3): 1087-1096, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35946529

RESUMO

OBJECTIVE: The most used drug for the treatment of rheumatoid arthritis (RA) remains methotrexate (MTX). Unfortunately, up to 50% of patients do not achieve a clinically adequate outcome. Here we study whether the gut microbiota patterns can aid in the prediction of MTX efficacy for RA. METHOD: To dissect gut microbiome profiles of RA patients (n = 145), 16S rRNA gene sequencing was performed. Dirichlet multinomial mixture (DMM) clustering was used to identify enterotypes at genus level. The relationships between enterotypes and clinical measures (such as lymphocyte subsets and cytokines detected by flow cytometry) were explored. Then, enterotype stability was evaluated by the stratification of the RA patient cohort (n = 66) in Shanghai, China, using the same method. Finally, the enterotype-based gut microbial human index classifier was applied to another independent RA patient cohort (n = 27) to identify the factors associated with MTX clinical response. RESULTS: Our analysis revealed that the RA patients always displayed two different dysbiotic microbiota patterns: RA E1 comprised predominantly Prevotella and RA E2 comprised predominantly Bacteroides. Among all of the lymphocyte subsets and cytokines, only the number of CD8+ T cells showed a significant difference between RA E1 and RA E2. These results were validated in the RA patient cohort in Shanghai, China. Significant associations of RA E1 with clinical response to subsequent MTX treatment were confirmed by another independent RA patient cohort. CONCLUSION: Together, the enterotype-based gut microbial human index (EGMI) classifier was useful to precisely and effectively identify enterotypes of individual RA patients, which could effectively evaluate MTX clinical responses.


Assuntos
Artrite Reumatoide , Microbioma Gastrointestinal , Humanos , Metotrexato/uso terapêutico , RNA Ribossômico 16S/genética , China , Artrite Reumatoide/tratamento farmacológico , Citocinas
3.
Rheumatol Ther ; 9(4): 1049-1059, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35499817

RESUMO

INTRODUCTION: Osteoporosis (OP) is one of the major comorbidities of rheumatoid arthritis (RA). Recent studies have shown that immune cells modulate bone health and regulate bone remodeling. However, the alterations of lymphocyte subsets in RA patients with OP are unclear. Here, we assessed the absolute numbers and proportions of the subsets in RA sufferers with OP and investigated the clinical significance. METHODS: A total of 777 RA patients and 117 gender- and age-matched healthy controls (HCs) were enrolled in this study. Patients were divided into RA-non-OP and RA-OP group according to their bone mineral density (BMD) and the history of fragility fracture. Peripheral lymphocyte subsets of participants were assessed by flow cytometry. RESULTS: Among 220 (28.31%) RA-OP patients, there were higher levels of erythrocyte sedimentation rate (ESR) (P = 0.011), C-reactive protein (CRP) (P = 0.028), rheumatoid factor (RF) (P = 0.013) and anti-cyclic citrullinated peptide antibody (ACPA) (P = 0.010), while red blood cells (RBC) (P = 0.039) were lower than those in RA-non-OP group. Compared with those of HCs and RA-non-OP group, the level of circulating Th17 cells in RA-OP patients was significantly increased (P < 0.05), while those of Tregs decreased (P < 0.01), leading to a higher ratio of Th17/Treg (P < 0.01). Notably, the level of B cells in both RA-non-OP and RA-OP group was reduced, this alteration was more obvious in patients with OP (P < 0.05). CONCLUSIONS: Immune disorders characterized by peripheral Th17/Treg imbalance and reduced B cells may contribute directly or indirectly to OP in RA, and this deserves more clinical attention.

4.
Arthritis Res Ther ; 24(1): 121, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606782

RESUMO

OBJECTIVE: Primary Sjogren's syndrome (pSS) is a heterogeneous chronic autoimmune disorder characterized by lymphocyte infiltration of the exocrine glands and the involvement and dysfunction of multiple organs and tissues. Interstitial lung disease (ILD) is the most common type of respiratory system damage. This study ascertained the factors related to ILD in patients with pSS (pSS-ILD), such as altered levels of circulating lymphocyte subtypes. METHODS: Eighty healthy controls and 142 patients diagnosed with pSS were included. The pSS patients were classified into groups with pSS-ILD or pSS without ILD (pSS-non-ILD). Baseline clinical and laboratory data were collected for all subjects, including the levels of lymphocytes measured by modified flow cytometry. RESULTS: The pSS-ILD patients were older, had higher ESSDAI scores, had higher positivity rates for anti-SSB and anti-Ro52 antibodies, and had more frequent symptoms of respiratory system involvement than pSS-non-ILD patients. pSS-ILD patients had the lowest Th2 cell counts among the three groups. Although the absolute numbers of Treg and NK cells were lower in pSS patients with and without ILD than in the healthy controls, there was no significant difference between the two pSS groups. The Th1/Th2 ratio was significantly higher in patients with ILD than in patients without ILD. Further analysis showed that older age (OR=1.084), lower Th2 count (OR=0.947), higher Th1/Th2 ratio (OR=1.021), and positivity for anti-SSB (OR=3.620) and anti-Ro52 (OR=5.184) antibodies were associated with the occurrence of ILD in patients with pSS. CONCLUSION: Decreased circulating Th2 cells and an elevated Th1/Th2 ratio may be the immunological mechanism underlying the development of ILD in pSS patients.


Assuntos
Doenças Pulmonares Intersticiais , Síndrome de Sjogren , Humanos , Doenças Pulmonares Intersticiais/complicações , Linfócitos , Estudos Retrospectivos , Síndrome de Sjogren/complicações , Síndrome de Sjogren/diagnóstico , Células Th2
5.
Adv Ther ; 39(7): 3280-3291, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35604524

RESUMO

INTRODUCTION: Rheumatoid arthritis (RA) is a chronic and refractory autoimmune disease characterized by synovial inflammation with unknown aetiology. Immune system dysfunction mediated by CD4+ T lymphocytes, which is regulated by the cytokine osteopontin (OPN), plays an important role in the pathogenesis of RA. METHODS: In this study, the levels of peripheral CD4+ T subsets and serum OPN in patients with active RA were measured and analysed to determine the possible pathogenesis of RA and to provide potential therapeutic targets. RESULTS: Serum OPN levels in both patients with active RA and patients with refractory RA were higher than those in healthy controls (HCs). Compared with HCs, the absolute numbers of Th2 cells increased in patients with active RA, while the absolute counts of Th1 and Treg cells decreased. There was no significant difference in CD4+ T subset levels between new-onset and refractory patients. As the condition persisted or deteriorated, a gradual increase in the levels of OPN and gradual declines in the absolute counts of Th1 and Treg cells were observed in patients with active RA. The fewest Th1 and Treg cells and the highest OPN levels were observed in patients with high disease activity. The serum OPN level was only significantly negatively correlated with the absolute counts of Treg cells in the CD4+ T lymphocyte subsets. CONCLUSIONS: Fewer Treg cells with the increase in disease activity may be related to the increased OPN concentration, which may provide new ideas and directions for the targeted immunoregulatory treatment of RA.


Assuntos
Artrite Reumatoide , Osteopontina , Linfócitos T Reguladores , Artrite Reumatoide/tratamento farmacológico , Citocinas , Progressão da Doença , Humanos , Osteopontina/uso terapêutico , Linfócitos T
6.
Ther Adv Musculoskelet Dis ; 13: 1759720X211011370, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995604

RESUMO

BACKGROUND: Circulating regulatory T cells (Tregs) are responsible for mediating immune tolerance and maintaining immunological homeostasis. Decreases in Tregs may be involved in the onset of rheumatoid arthritis (RA). Low-dose interleukin-2 (IL-2) has been considered for the treatment of inflammatory diseases mediated by T cells. This study focused on the status of circulating CD4+T subsets and the clinical feasibility of IL-2 therapies in patients with RA. METHODS: The subjects included 888 patients with RA and 100 healthy controls (HCs); 233 RA patients received IL-2 treatment with 0.5 million international units (MIU)/day from days 1 through 5. The demographic features, disease activity, and levels of CD4+T cells measured by modified flow cytometry were collected in all RA patients before and after treatment. RESULTS: RA patients had lower absolute Treg counts (but not Th17) compared with HCs, which was associated with disease activity; previously treated RA patients had the fewest circulating Tregs (p < 0.05). Patients treated with low-dose IL-2 had a three-fold increase in absolute anti-inflammatory Treg counts, as well as a two-fold increase in the other CD4+T subsets. Moreover, post-treatment levels of markers of disease activity in RA patients treated with IL-2 were significantly lower than the baseline values (p < 0.001), with no apparent side effects. CONCLUSION: Decreased absolute counts of circulating CD4+T lymphocyte subsets were observed in patients with RA. Circulating Tregs, which mediate immune tolerance, may be involved in the pathogenesis and progression of RA; however, this was ameliorated by low-dose IL-2, without obvious side effects. PLAIN LANGUAGE SUMMARY: Low-dose IL-2 treatment for rheumatoid arthritis • Circulating Tregs may be involved in the pathogenesis and progression of RA.• The absolute count of Tregs was significantly correlated with disease activity measures.• Low-dose IL-2 was able to effectively expade Tregs and help for RA patients' symptoms remission without evaluated side effects.

7.
Sci Rep ; 11(1): 3614, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33574432

RESUMO

Atherosclerosis is characterized by retention of modified lipoproteins, especially oxidized low density lipoprotein (oxLDL) within the sub-endothelial space of affected blood vessels. Recruited monocyte-derived and tissue-resident macrophages subsequently ingest oxLDL by binding and internalizing oxLDL via scavenger receptors, particularly CD36. The secreted neurorepellent, Slit2, acting through its transmembrane receptor, Roundabout-1 (Robo-1), was previously shown to inhibit recruitment of monocytes into nascent atherosclerotic lesions. The effects of Slit2 on oxLDL uptake by macrophages have not been explored. We report here that Slit2 inhibits uptake of oxLDL by human and murine macrophages, and the resulting formation of foam cells, in a Rac1-dependent and CD36-dependent manner. Exposure of macrophages to Slit2 prevented binding of oxLDL to the surface of cells. Using super-resolution microscopy, we observed that exposure of macrophages to Slit2 induced profound cytoskeletal remodeling with formation of a thick ring of cortical actin within which clusters of CD36 could not aggregate, thereby attenuating binding of oxLDL to the surface of cells. By inhibiting recruitment of monocytes into early atherosclerotic lesions, and the subsequent binding and internalization of oxLDL by macrophages, Slit2 could represent a potent new tool to combat individual steps that collectively result in progression of atherosclerosis.


Assuntos
Aterosclerose/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Lipídeos/imunologia , Lipoproteínas LDL/genética , Proteínas do Tecido Nervoso/genética , Animais , Aterosclerose/imunologia , Aterosclerose/patologia , Vasos Sanguíneos/imunologia , Antígenos CD36/genética , Antígenos CD36/imunologia , Modelos Animais de Doenças , Células Espumosas , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Lipídeos/genética , Lipoproteínas LDL/imunologia , Macrófagos/imunologia , Camundongos , Monócitos/imunologia , Proteínas do Tecido Nervoso/metabolismo , Receptores Depuradores/genética , Receptores Depuradores/imunologia
8.
Front Immunol ; 12: 768244, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35006213

RESUMO

Background: Takayasu's arteritis (TA) is a type of primary large vessel vasculitis. Th1, Th17, and Tfh cells have been reported to be associated with TA relapse. However, the relationship between regulatory T cells (Tregs) and TA remains unclear. Objective: To analyze the levels of circulating lymphocytes, especially Treg cells (CD4+CD25+FOXP3+ T cells) and serum cytokines in TA patients and explore their relationship with their changes and TA disease activity. Methods: A total of 57 TA patients and 43 sex- and age-matched healthy controls (HCs) were enrolled. According to NIH standards, 36 patients had active disease status. Flow cytometry combined with counting was used to detect the absolute numbers and ratios of Th1, Th2, Th17, and Treg cells in the peripheral blood of all the subjects. Magnetic bead-based multiplex immunoassay was used to detect cytokines. Results: Compared to HCs, the absolute number and proportion of peripheral Treg cells in TA patients was significantly decreased, while Th17 cells were significantly increased. Furthermore, compared to the inactive group, the TA active group had significantly increased levels of interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α, but lower IL-10 levels. The absolute number of Th2 cells was negatively associated with platelet (PLT) and NIS scores in TA patients. The proportion of Th2 cells was negatively associated with the erythrocyte sedimentation rate in TA patients. After treatment, Treg cells were markedly increased. Conclusion: There was a Th17-Treg cell imbalance with a significant reduction in peripheral Treg cells and an increase in Th17 cells in TA patients compared to the HCs. The levels of IL-6, IL-10, IL-17, and TNF-α appeared to be related to disease activity.


Assuntos
Linfócitos T Reguladores/imunologia , Arterite de Takayasu/imunologia , Adolescente , Adulto , Sedimentação Sanguínea , Citocinas/biossíntese , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Células Th2/imunologia , Adulto Jovem
10.
Nat Commun ; 11(1): 4112, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807784

RESUMO

Macropinocytosis is essential for myeloid cells to survey their environment and for growth of RAS-transformed cancer cells. Several growth factors and inflammatory stimuli are known to induce macropinocytosis, but its endogenous inhibitors have remained elusive. Stimulation of Roundabout receptors by Slit ligands inhibits directional migration of many cell types, including immune cells and cancer cells. We report that SLIT2 inhibits macropinocytosis in vitro and in vivo by inducing cytoskeletal changes in macrophages. In mice, SLIT2 attenuates the uptake of muramyl dipeptide, thereby preventing NOD2-dependent activation of NF-κB and consequent secretion of pro-inflammatory chemokine, CXCL1. Conversely, blocking the action of endogenous SLIT2 enhances CXCL1 secretion. SLIT2 also inhibits macropinocytosis in RAS-transformed cancer cells, thereby decreasing their survival in nutrient-deficient conditions which resemble tumor microenvironment. Our results identify SLIT2 as a physiological inhibitor of macropinocytosis and challenge the conventional notion that signals that enhance macropinocytosis negatively regulate cell migration, and vice versa.


Assuntos
Citoesqueleto/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores Imunológicos/metabolismo , Animais , Quimiocina CXCL1/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/genética , Macrófagos/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteínas do Tecido Nervoso/genética , Fagócitos/metabolismo , Pinocitose/genética , Pinocitose/fisiologia , Receptores Imunológicos/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteína rhoA de Ligação ao GTP/metabolismo , Proteínas Roundabout
11.
Can Respir J ; 2019: 7262065, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885749

RESUMO

Objective: The absolute and relative changes of peripheral NK and T subsets are unclear in rheumatoid arthritis (RA) associated with pulmonary interstitial fibrosis (RA-ILD). To investigate the clinical risk factors, especially the changes of lymphocyte subsets, in RA-ILD in order to make early diagnosis and achieve prevention of the pulmonary interstitial lesions. Methods: A total of 100 RA and 100 RA-ILD patients were enrolled. Rheumatoid factor, anti-cyclic citrulline peptide antibody, erythrocyte sedimentation rate, immunoglobulin, and C-reactive protein were examined. The percentage and absolute number of NK, T, B, Treg, Th1, Th2, and Th17 cells in peripheral blood were determined by flow cytometry. Results: RA-ILD is more common in older and male RA patients and/or those with higher autoantibody titers. Flow cytometry showed that the absolute and relative numbers of CD56+ NK cells were significantly higher in RA-ILD (280.40 ± 180.51 cells/µl vs. 207.66 ± 148.57 cells/µl; 16.62 ± 8.56% vs. 12.11 ± 6.47%), whereas the proportion of T cells and CD4+ T cells was lower in peripheral blood of RA-ILD patients (69.82 ± 9.30%; 39.44 ± 9.87 cells/µl) than that in RA patients (74.45 ± 8.72%; 43.29 ± 9.10 cells/µl). Conclusions: The occurrence of RA-ILD is closely related to the older male patients with high titer of various self-antibodies. Imbalance of CD3-CD56+ NK cells and T cells with other subsets were found in RA-ILD patients, which, together with older age, male, and high levels of autoantibodies should be considered as risk factors of pulmonary interstitial lesions.


Assuntos
Anticorpos Antiproteína Citrulinada/imunologia , Artrite Reumatoide/imunologia , Células Matadoras Naturais/imunologia , Doenças Pulmonares Intersticiais/imunologia , Fibrose Pulmonar/imunologia , Fator Reumatoide/imunologia , Linfócitos T/imunologia , Adulto , Fatores Etários , Idoso , Artrite Reumatoide/complicações , Linfócitos B/imunologia , Sedimentação Sanguínea , Proteína C-Reativa/imunologia , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Doenças Pulmonares Intersticiais/complicações , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Fibrose Pulmonar/complicações , Fatores Sexuais , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia
12.
J Immunol Res ; 2019: 7684352, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781682

RESUMO

BACKGROUND: We have reported previously the insufficient absolute number or functional defects of regulatory T cells (Tregs) in patients with rheumatoid arthritis (RA), challenging conventional unspecific immunosuppressive therapy. Sirolimus, a mTOR inhibitor, is reported to allow growth of functional Tregs; here, we investigated the efficacy of low-dose sirolimus combined with conventional immunosuppressants (sirolimus immunoregulation therapy) for RA treatment with lower side effects and better tolerance. METHODS: In this nonblinded and parallel-group trial, we randomly assigned 62 patients to receive conventional glucocorticoids and immunosuppressants with or without sirolimus at a dosage of 0.5 mg on alternate days for 24 weeks in a 2 : 1 ratio. The demographic features, clinical manifestations, and laboratory indicators including peripheral blood lymphocyte subgroups and CD4+T subsets were compared before and after the treatment. RESULTS: Finally, 37 patients in the sirolimus group and 18 in the conventional treated group completed the 6-month study. By 24 weeks, the patients with sirolimus experienced significant reduction in disease activity indicators including DAS28, ESR, and the number of tender joints and swollen joints (p < 0.001). Notably, they had a higher level of Tregs as compared with those with conventional therapy alone (p < 0.05), indicating that sirolimus could partly restore the reduced Tregs. Concomitantly, their usage of immunosuppressants for controlling disease activity was decreased as compared with the conventional group with no difference in blood routine, and liver and renal functions both before and after the treatment of sirolimus and between the two groups (p > 0.05). CONCLUSIONS: Low-dose sirolimus immunoregulatory therapy selectively upregulated Tregs and partly replaced the usage of immunosuppressants to control disease activity without overtreatment and evaluable side effect. Further study is required using a large sample of RA patients treated with sirolimus for a longer period. This trial is registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/showproj.aspx?proj=17245).


Assuntos
Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Imunomodulação/efeitos dos fármacos , Imunossupressores/administração & dosagem , Sirolimo/administração & dosagem , Adulto , Artrite Reumatoide/diagnóstico , Biomarcadores , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Resultado do Tratamento
13.
J Am Soc Nephrol ; 27(9): 2609-15, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26869008

RESUMO

Fibrosis and inflammation are closely intertwined injury pathways present in nearly all forms of CKD for which few safe and effective therapies exist. Slit glycoproteins signaling through Roundabout (Robo) receptors have been described to have anti-inflammatory effects through regulation of leukocyte cytoskeletal organization. Notably, cytoskeletal reorganization is also required for fibroblast responses to TGF-ß Here, we examined whether Slit2 also controls TGF-ß-induced renal fibrosis. In cultured renal fibroblasts, which we found to express Slit2 and Robo-1, the bioactive N-terminal fragment of Slit2 inhibited TGF-ß-induced collagen synthesis, actin cytoskeletal reorganization, and Smad2/3 transcriptional activity, but the inactive C-terminal fragment of Slit2 did not. In mouse models of postischemic renal fibrosis and obstructive uropathy, treatment with N-terminal Slit2 before or after injury inhibited the development of renal fibrosis and preserved renal function, whereas the C-terminal Slit2 had no effect. Our data suggest that administration of recombinant Slit2 may be a new treatment strategy to arrest chronic injury progression after ischemic and obstructive renal insults by not only attenuating inflammation but also, directly inhibiting renal fibrosis.


Assuntos
Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Nefropatias/prevenção & controle , Rim/patologia , Proteínas do Tecido Nervoso/farmacologia , Proteínas do Tecido Nervoso/uso terapêutico , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/fisiologia , Animais , Fibrose/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes
14.
J Immunol ; 195(7): 3334-44, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26297762

RESUMO

The secreted neurorepellent Slit2, acting through its transmembrane receptor, Roundabout (Robo)-1, inhibits chemotaxis of varied cell types, including leukocytes, endothelial cells, and vascular smooth muscle cells, toward diverse attractants. The role of Slit2 in regulating the steps involved in recruitment of monocytes in vascular inflammation is not well understood. In this study, we showed that Slit2 inhibited adhesion of monocytic cells to activated human endothelial cells, as well as to immobilized ICAM-1 and VCAM-1. Microfluidic live cell imaging showed that Slit2 inhibited the ability of monocytes tethered to endothelial cells to stabilize their actin-associated anchors and to resist detachment in response to increasing shear forces. Transfection of constitutively active plasmids revealed that Slit2 inhibited postadhesion stabilization of monocytes on endothelial cells by preventing activation of Rac1. We further found that Slit2 inhibited chemotaxis of monocytes toward CXCL12 and CCL2. To determine whether Slit2 and Robo-1 modulate pathologic monocyte recruitment associated with vascular inflammation and cardiovascular disease, we tested PBMC from patients with coronary artery disease. PBMC from these patients had reduced surface levels of Robo-1 compared with healthy age- and sex-matched subjects, and Slit2 failed to inhibit chemotaxis of PBMC of affected patients, but not healthy control subjects, toward CCL2. Furthermore, administration of Slit2 to atherosclerosis-prone LDL receptor-deficient mice inhibited monocyte recruitment to nascent atherosclerotic lesions. These results demonstrate that Slit2 inhibits chemotaxis of monocytes, as well as their ability to stabilize adhesions and resist detachment forces. Slit2 may represent a powerful new tool to inhibit pathologic monocyte recruitment in vascular inflammation and atherosclerosis.


Assuntos
Adesão Celular/fisiologia , Quimiotaxia de Leucócito/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Monócitos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores Imunológicos/metabolismo , Animais , Aterosclerose/patologia , Doenças Cardiovasculares/imunologia , Linhagem Celular , Quimiocina CCL2 , Quimiocina CXCL12 , Ativação Enzimática , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamação/imunologia , Molécula 1 de Adesão Intercelular/metabolismo , Leucócitos Mononucleares/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Monócitos/imunologia , Receptores de LDL/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas Roundabout
15.
PLoS One ; 8(11): e79203, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24236110

RESUMO

BACKGROUND: Although transfusion-transmitted infection of hepatitis B virus (HBV) threatens the blood safety of China, the nationwide circumstance of HBV infection among blood donors is still unclear. OBJECTIVES: To comprehensively estimate the prevalence of HBsAg positive and HBV occult infection (OBI) among Chinese volunteer blood donors through bayesian meta-analysis. METHODS: We performed an electronic search in Pub-Med, Web of Knowledge, Medline, Wanfang Data and CNKI, complemented by a hand search of relevant reference lists. Two authors independently extracted data from the eligible studies. Then two bayesian random-effect meta-analyses were performed, followed by bayesian meta-regressions. RESULTS: 5957412 and 571227 donors were identified in HBsAg group and OBI group, respectively. The pooled prevalence of HBsAg group and OBI group among donors is 1.085% (95% credible interval [CI] 0.859%~1.398%) and 0.094% (95% CI 0.0578%~0.1655%). For HBsAg group, subgroup analysis shows the more developed area has a lower prevalence than the less developed area; meta-regression indicates there is a significant decreasing trend in HBsAg positive prevalence with sampling year (beta = -0.1202, 95% -0.2081~-0.0312). CONCLUSION: Blood safety against HBV infection in China is suffering serious threats and the government should take effective measures to improve this situation.


Assuntos
Doadores de Sangue , Vírus da Hepatite B , Hepatite B/epidemiologia , Teorema de Bayes , China , Geografia , Humanos , Prevalência
16.
J Am Soc Nephrol ; 24(8): 1274-87, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23766538

RESUMO

Neutrophils recruited to the postischemic kidney contribute to the pathogenesis of ischemia-reperfusion injury (IRI), which is the most common cause of renal failure among hospitalized patients. The Slit family of secreted proteins inhibits chemotaxis of leukocytes by preventing activation of Rho-family GTPases, suggesting that members of this family might modulate the recruitment of neutrophils and the resulting IRI. Here, in static and microfluidic shear assays, Slit2 inhibited multiple steps required for the infiltration of neutrophils into tissue. Specifically, Slit2 blocked the capture and firm adhesion of human neutrophils to inflamed vascular endothelial barriers as well as their subsequent transmigration. To examine whether these observations were relevant to renal IRI, we administered Slit2 to mice before bilateral clamping of the renal pedicles. Assessed at 18 hours after reperfusion, Slit2 significantly inhibited renal tubular necrosis, neutrophil and macrophage infiltration, and rise in plasma creatinine. In vitro, Slit2 did not impair the protective functions of neutrophils, including phagocytosis and superoxide production, and did not inhibit neutrophils from killing the extracellular pathogen Staphylococcus aureus. In vivo, administration of Slit2 did not attenuate neutrophil recruitment or bacterial clearance in mice with ascending Escherichia coli urinary tract infections and did not increase the bacterial load in the livers of mice infected with the intracellular pathogen Listeria monocytogenes. Collectively, these results suggest that Slit2 may hold promise as a strategy to combat renal IRI without compromising the protective innate immune response.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Creatinina/sangue , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Rim/irrigação sanguínea , Proteínas do Tecido Nervoso/administração & dosagem , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Traumatismo por Reperfusão/complicações , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Animais , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Rim/imunologia , Rim/patologia , Camundongos , Proteínas do Tecido Nervoso/fisiologia , Infiltração de Neutrófilos/imunologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia
17.
Br J Ophthalmol ; 97(4): 389-94, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23143904

RESUMO

BACKGROUND: Epidemiologists have recently investigated sunlight exposure as a risk factor for age-related macular degeneration (AMD), but there remains an ongoing dispute over this association due to insufficient evidence and unreliable data. OBJECTIVES: To analyse comprehensively the epidemiological literature concerning the association between AMD and sunlight exposure. METHODS: We systematically reviewed the epidemiological literature concerning the association between AMD and sunlight exposure. An electronic search was performed of PubMed, Web of Science and CNKI, which was supplemented by hand searching. The selection of studies, data abstraction and quality assessment were performed independently by three reviewers. After these steps, we performed a random-effects meta-analysis, followed by subgroup analysis and sensitivity analysis, including a random-effects meta-regression for study-specific covariates. RESULTS: Fourteen studies were identified. Twelve studies identified an increasing risk of AMD with greater sunlight exposure, six of which reported significant risks. The pooled OR was 1.379 (95% CI 1.091 to 1.745). The subgroup of non-population-based studies revealed a significant risk (OR 2.018, 1.248 to 3.265, p=0.004). We identified the gross domestic product (GDP) per capita (p=0.048), but not the latitude (p=0.21), as a factor that led to heterogeneity according to the meta-regression. CONCLUSIONS: The epidemiological literature published to date indicates that individuals with more sunlight exposure are at a significantly increased risk of AMD. The OR significantly decreased with increasing GDP per capita.


Assuntos
Exposição Ambiental/efeitos adversos , Macula Lutea/efeitos da radiação , Degeneração Macular/etiologia , Lesões por Radiação/etiologia , Luz Solar/efeitos adversos , Humanos , Fatores de Risco
18.
Circulation ; 126(11): 1385-95, 2012 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-22865890

RESUMO

BACKGROUND: Vascular injury and atherothrombosis involve vessel infiltration by inflammatory leukocytes, migration of medial vascular smooth muscle cells to the intimal layer, and ultimately acute thrombosis. A strategy to simultaneously target these pathological processes has yet to be identified. The secreted protein, Slit2, and its transmembrane receptor, Robo-1, repel neuronal migration in the developing central nervous system. More recently, it has been appreciated that Slit2 impairs chemotaxis of leukocytes and vascular smooth muscle cells toward diverse inflammatory attractants. The effects of Slit2 on platelet function and thrombus formation have never been explored. METHODS AND RESULTS: We detected Robo-1 expression in human and murine platelets and megakaryocytes and confirmed its presence via immunofluorescence microscopy and flow cytometry. In both static and shear microfluidic assays, Slit2 impaired platelet adhesion and spreading on diverse extracellular matrix substrates by suppressing activation of Akt. Slit2 also prevented platelet activation on exposure to ADP. In in vivo studies, Slit2 prolonged bleeding times in murine tail bleeding assays. Using intravital microscopy, we found that after mesenteric arteriolar and carotid artery injury, Slit2 delayed vessel occlusion time and prevented the stable formation of occlusive arteriolar thrombi. CONCLUSIONS: These data demonstrate that Slit2 is a powerful negative regulator of platelet function and thrombus formation. The ability to simultaneously block multiple events in vascular injury may allow Slit2 to effectively prevent and treat thrombotic disorders such as myocardial infarction and stroke.


Assuntos
Plaquetas/fisiologia , Movimento Celular/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Animais , Trombose das Artérias Carótidas/induzido quimicamente , Trombose das Artérias Carótidas/fisiopatologia , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Cloretos/efeitos adversos , Compostos Férricos/efeitos adversos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Proteínas do Tecido Nervoso/farmacologia , Adesividade Plaquetária/fisiologia , Receptores Imunológicos/fisiologia , Fatores de Risco , Proteínas Roundabout
19.
J Am Soc Nephrol ; 23(1): 27-35, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22052054

RESUMO

Notch signaling in podocytes causes proteinuria and glomerulosclerosis in humans and rodents, but the underlying mechanism remains unknown. Here, we analyzed morphologic, molecular, and cellular events before the onset of proteinuria in newborn transgenic mice that express activated Notch in podocytes. Immunohistochemistry revealed a loss of the slit diaphragm protein nephrin exclusively in podocytes expressing activated Notch. Podocyte-specific deletion of Rbpj, which is essential for canonical Notch signaling, prevented this loss of nephrin. Overexpression of activated Notch decreased cell surface nephrin and increased cytoplasmic nephrin in transfected HEK293T cells; pharmacologic inhibition of dynamin, but not depletion of cholesterol, blocked these effects on nephrin, suggesting that Notch promotes dynamin-dependent, raft-independent endocytosis of nephrin. Supporting an association between Notch signaling and nephrin trafficking, electron microscopy revealed shortened podocyte foot processes and fewer slit diaphragms among the transgenic mice compared with controls. These data suggest that Notch signaling induces endocytosis of nephrin, thereby triggering the onset of proteinuria.


Assuntos
Endocitose , Proteínas de Membrana/metabolismo , Podócitos/metabolismo , Proteinúria/etiologia , Receptores Notch/metabolismo , Animais , Animais Recém-Nascidos , Dinaminas/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Transgênicos , Podócitos/ultraestrutura , Proteinúria/metabolismo , Proteinúria/patologia , Transdução de Sinais , beta-Ciclodextrinas
20.
J Insect Sci ; 11: 135, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22243438

RESUMO

The silkworm, Bombyx mori L. (Lepidoptera: Bombycidae), an oligophagous insect that mainly feeds on mulberry leaves, is susceptible to entomopathogen infection when reared with tricuspid cudrania leaves. A total of 56 dominant bacterial strains, classified into 12 phylotypes based on bacteriological properties and analysis of 16S rRNA genes, were isolated from the intestine of the fourth and fifth instar silkworm larvae. Ten and seven phylotypes exist in the intestine of the silkworm larvae reared with mulberry leaves and tricuspid cudrania leaves, respectively. Four of them are common in the intestine of the two treatment groups. By screening their lipolytic ability on a Rhodamine B agar plate, nine lipase-producing bacterial strains were obtained and classified into six genera, including Bacillus, Brevibacterium, Corynebacterium, Staphylococcus, Klebsiella, and Stenotrophomonas. Except for Stenotrophomonas, which is common in both, the other genera only exist in the intestine of the silkworm larvae fed with mulberry leaves. In addition, by culture and fermentation in vitro, the maximum cell density and lipase activity of lipase-producing bacteria were examined at about 48 hours. The results indicate that diet has a significant impact on the gut bacterial community, especially lipase-producing bacteria. We suggest that the difference of lipase-producing bacterial diversity might be related to disease resistance of the silkworm.


Assuntos
Bactérias/isolamento & purificação , Bombyx/microbiologia , Lipase/análise , Moraceae , Animais , Bactérias/enzimologia , Bactérias/genética , Bombyx/imunologia , DNA Bacteriano/genética , Dieta , Trato Gastrointestinal/microbiologia , Herbivoria , RNA Ribossômico 16S/genética
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