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1.
IEEE Trans Biomed Eng ; 71(5): 1607-1616, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38285584

RESUMO

OBJECTIVE: The study aims to investigate the relationship between amplitude modulation (AM) of EEG and anesthesia depth during general anesthesia. METHODS: In this study, Holo-Hilbert spectrum analysis (HHSA) was used to decompose the multichannel EEG signals of 15 patients to obtain the spatial distribution of AM in the brain. Subsequently, HHSA was applied to the prefrontal EEG (Fp1) obtained during general anesthesia surgery in 15 and 34 patients, and the α-θ and α-δ regions of feature (ROFs) were defined in Holo-Hilbert spectrum (HHS) and three features were derived to quantify AM in ROFs. RESULTS: During anesthetized phase, an anteriorization of the spatial distribution of AMs of α-carrier in brain was observed, as well as AMs of α-θ and α-δ in the EEG of Fp1. The total power ([Formula: see text]), mean carrier frequency ([Formula: see text]) and mean amplitude frequency ([Formula: see text]) of AMs changed during different anesthesia states. CONCLUSION: HHSA can effectively analyze the cross-frequency coupling of EEG during anesthesia and the AM features may be applied to anesthesia monitoring. SIGNIFICANCE: The study provides a new perspective for the characterization of brain states during general anesthesia, which is of great significance for exploring new features of anesthesia monitoring.


Assuntos
Anestesia Geral , Eletroencefalografia , Processamento de Sinais Assistido por Computador , Humanos , Eletroencefalografia/métodos , Anestesia Geral/métodos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Encéfalo/fisiologia , Algoritmos , Adulto Jovem , Idoso , Monitorização Intraoperatória/métodos
2.
J Thromb Haemost ; 22(4): 1145-1153, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38103733

RESUMO

BACKGROUND: Adenoviral vector-based COVID-19 vaccine-induced immune thrombotic thrombocytopenia (VITT) is rare but carries significant risks of mortality and long-term morbidity. The underlying pathophysiology of severe disease is still not fully understood. The objectives were to explore the pathophysiological profile and examine for clinically informative biomarkers in patients with severe VITT. METHODS: Twenty-two hospitalized patients with VITT, 9 pre- and 21 post-ChAdOx1 vaccine controls, were recruited across England, United Kingdom. Admission blood samples were analyzed for cytokine profiles, cell death markers (lactate dehydrogenase and circulating histones), neutrophil extracellular traps, and coagulation parameters. Tissue specimens from deceased patients were analyzed. RESULTS: There were strong immune responses characterized by significant elevations in proinflammatory cytokines and T helper 1 and 2 cell activation in patients with VITT. Markers of systemic endothelial activation and coagulation activation in both circulation and organ sections were also significantly elevated. About 70% (n = 15/22) of patients met the International Society for Thrombosis and Haemostasis criteria for disseminated intravascular coagulation despite negligible changes in the prothrombin time. The increased neutrophil extracellular trap formation, in conjunction with marked lymphopenia, elevated lactate dehydrogenase, and circulating histone levels, indicates systemic immune cell injury or death. Both lymphopenia and circulating histone levels independently predicted 28-day mortality in patients with VITT. CONCLUSION: The coupling of systemic cell damage and death with strong immune-inflammatory and coagulant responses are pathophysiologically dominant and clinically relevant in severe VITT.


Assuntos
Linfopenia , Púrpura Trombocitopênica Idiopática , Trombocitopenia , Trombose , Vacinas , Humanos , Histonas , Vacinas contra COVID-19/efeitos adversos , Lactato Desidrogenases
3.
Biomolecules ; 13(7)2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37509135

RESUMO

Most patients who die of cancer do so from its metastasis to other organs. The calcium-binding protein S100A4 can induce cell migration/invasion and metastasis in experimental animals and is overexpressed in most human metastatic cancers. Here, we report that a novel inhibitor of S100A4 can specifically block its increase in cell migration in rat (IC50, 46 µM) and human (56 µM) triple negative breast cancer (TNBC) cells without affecting Western-blotted levels of S100A4. The moderately-weak S100A4-inhibitory compound, US-10113 has been chemically attached to thalidomide to stimulate the proteasomal machinery of a cell. This proteolysis targeting chimera (PROTAC) RGC specifically eliminates S100A4 in the rat (IC50, 8 nM) and human TNBC (IC50, 3.2 nM) cell lines with a near 20,000-fold increase in efficiency over US-10113 at inhibiting cell migration (IC50, 1.6 nM and 3.5 nM, respectively). Knockdown of S100A4 in human TNBC cells abolishes this effect. When PROTAC RGC is injected with mouse TNBC cells into syngeneic Balb/c mice, the incidence of experimental lung metastases or local primary tumour invasion and spontaneous lung metastasis is reduced in the 10-100 nM concentration range (Fisher's Exact test, p ≤ 0.024). In conclusion, we have established proof of principle that destructive targeting of S100A4 provides the first realistic chemotherapeutic approach to selectively inhibiting metastasis.


Assuntos
Proteína A4 de Ligação a Cálcio da Família S100 , Neoplasias de Mama Triplo Negativas , Animais , Humanos , Camundongos , Ratos , Linhagem Celular Tumoral , Movimento Celular , Invasividade Neoplásica , Metástase Neoplásica , Proteína A4 de Ligação a Cálcio da Família S100/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Quimera de Direcionamento de Proteólise/metabolismo , Quimera de Direcionamento de Proteólise/farmacologia
4.
J Thromb Haemost ; 21(7): 1724-1736, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37116754

RESUMO

The cell-based model of coagulation remains the basis of our current understanding of clinical hemostasis and thrombosis. Its advancement on the coagulation cascade model has enabled new prohemostatic and anticoagulant treatments to be developed. In the past decade, there has been increasing evidence of the procoagulant properties of extracellular, cell-free histones (CFHs). Although high levels of circulating CFHs released following extensive cell death in acute critical illnesses, such as sepsis and trauma, have been associated with adverse coagulation outcomes, including disseminated intravascular coagulation, new information has also emerged on how its local effects contribute to physiological clot formation. CFHs initiate coagulation by tissue factor exposure, either by destruction of the endovascular barrier or induction of endoluminal tissue factor expression on endothelia and monocytes. CFHs can also bind prothrombin directly, generating thrombin via the alternative prothrombinase pathway. In amplifying and augmenting the procoagulant signal, CFHs activate and aggregate platelets, increase procoagulant material bioavailability through platelet degranulation and Weibel-Palade body exocytosis, activate intrinsic coagulation via platelet polyphosphate release, and induce phosphatidylserine exposure. CFHs also inhibit protein C activation and downregulate thrombomodulin expression to reduce anti-inflammatory and anticoagulant effects. In consolidating clot formation, CFHs augment the fibrin polymer to confer fibrinolytic resistance and integrate neutrophil extracellular traps into the clot structure. Such new information holds the promise of new therapeutic developments, including improved targeting of immunothrombotic pathologies in acute critical illnesses.


Assuntos
Histonas , Trombose , Humanos , Histonas/metabolismo , Tromboplastina/metabolismo , Estado Terminal , Coagulação Sanguínea/fisiologia , Trombose/metabolismo , Anticoagulantes
5.
Comput Biol Med ; 147: 105687, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35687924

RESUMO

BACKGROUND: Recent studies have demonstrated that changes in brain information processing during anesthetic-induced loss of consciousness (LOC) might be influenced by phase-amplitude coupling (PAC) in electroencephalogram (EEG). However, most anesthesia research on PAC typically focuses on delta and alpha oscillations. Studies of spatial-frequency characteristics by PAC for EEG may yield additional insights into understanding the impaired information processing under anesthesia unconsciousness and provide potential improvements in anesthesia monitoring. OBJECTIVE: Considering different frequency bands of EEG represent neural activities on different spatial scales, we hypothesized that functional coupling simultaneously appears in multiple frequency bands and specific brain regions during anesthesia unconsciousness. In this paper, PAC analysis on whole-brain EEG besides delta and alpha oscillations was investigated to understand the influence of multiple cross-frequency coordination coupling on information processing during the loss and recovery of consciousness. METHOD: EEG data from fifteen patients without cognitive diseases (7 males/8 females, aged 43.8 ± 13.4 years, weighing 63.3 ± 14.9 kilograms) undergoing lower limb surgery and sevoflurane anesthesia was recorded. To investigate the spatial-frequency characteristics of EEG source signals during loss and recovery of consciousness, the time-resolved PAC (tPAC) was calculated to reflect cross-frequency coordination in different frequency bands (delta, theta, alpha, beta, gamma) and different functional regions (Visual, Limbic, Dorsal attention, Ventral attention, Default, Somatomotor, Control, Salience networks). Furthermore, different patterns (peak-max and trough-max) of PAC were examined by constructing phase-amplitude histograms using phase bins to investigate the different information processing during LOC. The multivariate analysis of variance (MANOVA) and trend analysis were used for statistical analysis. RESULTS: Theta-alpha and alpha-beta PAC were observed during sevoflurane-induced LOC, which significantly changed during loss and recovery of consciousness (F4,70 = 16.553, p < 0.001 for theta-alpha PAC and F4,70 = 12.446, p < 0.001 for alpha-beta PAC, MANOVA test). Simultaneously, PAC was distributed in specific functional regions, i.e., Visual, Limbic, Default, Somatomotor, etc. Furthermore, peak-max patterns of theta-alpha PAC were observed while alpha-beta PAC showed trough-max patterns and vice versa. CONCLUSION: Theta-alpha and alpha-beta PAC observed in specific brain regions represent information processing on multiple spatial scales, and the opposite patterns of PAC indicate opposite information processing on multiple spatial scales during LOC. Our study demonstrates the regulation of local-global information processing during sevoflurane-induced LOC. It suggests the utility of evaluating the balance of functional integration and segregation in monitoring anesthetized states.


Assuntos
Estado de Consciência , Inconsciência , Encéfalo/fisiologia , Estado de Consciência/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Sevoflurano/efeitos adversos , Inconsciência/induzido quimicamente
6.
Clin Med (Lond) ; 22(2): 140-144, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35273026

RESUMO

In the new science emanating from the COVID-19 pandemic, effective vaccine development has made a huge difference and saved countless lives. Vaccine roll-out led to the identification of rare cases of severe thrombotic and thrombocytopenic problems in some recipients. This apparent coupling of thrombosis with haemorrhagic potentiation might seem baffling but the ensuing clinical investigation rapidly shed important light on its molecular mechanism. This review outlines the current understanding on the role of adenovirus-based platforms, the immunogenic triggers and the immunothrombotic response underlying vaccine-induced immune thrombotic thrombocytopenia.


Assuntos
COVID-19 , Trombocitopenia , Trombose , Vacinas , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Humanos , Pandemias , SARS-CoV-2 , Trombocitopenia/induzido quimicamente , Vacinas/efeitos adversos
7.
Br J Anaesth ; 128(2): 283-293, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34893315

RESUMO

BACKGROUND: Neutrophil extracellular traps (NETs) facilitate bacterial clearance but also promote thrombosis and organ injury in sepsis. We quantified ex vivo NET induction in septic humans and murine models of sepsis to identify signalling pathways that may be modulated to improve outcome in human sepsis. METHODS: NET formation in human donor neutrophils was quantified after incubation with plasma obtained from patients with sepsis or systemic inflammation (double-blinded assessment of extracellular DNA using immunofluorescence microscopy). NET formation (% neutrophils forming NETs) was correlated with plasma cytokine levels (MultiPlex assay). Experimental sepsis (caecal ligation and puncture or intraperitoneal injection of Escherichia coli) was assessed in C57/BL6 male mice. The effect of pharmacological inhibition of CXCR1/2 signalling (reparixin) on NET formation, organ injury (hepatic, renal, and cardiac biomarkers), and survival in septic mice was examined. RESULTS: NET formation was higher after incubation with plasma from septic patients (median NETs=25% [10.5-46.5%]), compared with plasma obtained from patients with systemic inflammation (14% [4.0-23.3%]; P=0.02). Similar results were observed after incubation of plasma from mice with neutrophils from septic non-septic mice. Circulating CXCR1/2 ligands correlated with NETosis in patients (interleukin-8; r=0.643) and mice (macrophage inflammatory protein-2; r=0.902). In experimental sepsis, NETs were primarily observed in the lungs, correlating with fibrin deposition (r=0.702) and lung injury (r=0.692). Inhibition of CXCR1/2 using reparixin in septic mice reduced NET formation, multi-organ injury, and mortality, without impairing bacterial clearance. CONCLUSION: CXCR1/2 signalling-induced NET formation is a therapeutic target in sepsis, which may be guided by ex vivo NET assays.


Assuntos
Armadilhas Extracelulares/metabolismo , Inflamação/complicações , Sepse/complicações , Sulfonamidas/farmacologia , Trombose/prevenção & controle , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Inflamação/tratamento farmacológico , Lesão Pulmonar/etiologia , Lesão Pulmonar/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/metabolismo , Receptores de Interleucina-8A/antagonistas & inibidores , Receptores de Interleucina-8B/antagonistas & inibidores , Estudos Retrospectivos , Sepse/tratamento farmacológico , Sepse/mortalidade , Trombose/etiologia
8.
Front Pharmacol ; 12: 709060, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733154

RESUMO

Aim: This study aimed to report the efficacy and safety of trans-arterial chemoembolization (TACE) plus lenvatinib and camrelizumab in patients with advanced hepatocellular carcinoma (HCC). Methods: This retrospective study enrolled 22 patients with advanced HCC from March 2018 to December 2019. All the patients received comprehensive treatment with TACE plus lenvatinib followed by camrelizumab. Overall survival (OS) and progression-free survival (PFS) were calculated and analysed using the Kaplan-Meier method and log-rank test. Treatment response and adverse events (AEs) were also evaluated. Results: The objective response rate (ORR) and disease control rate (DCR) for the whole cohort were 68.2 and 100% at the first month and 72.7 and 95.5% at the third month, respectively. The median OS was 24 months (95% CI, 20.323-27.677 months), and the median PFS was 11.4 months (95% CI, 8.846-13.954 months). The majority of treatment-related adverse reactions were mild or moderate, except for 4 that developed to grade 3-4 (3 reactions of grade 3, 1 reaction of grade 4). No deaths or other serious adverse reactions occurred. Conclusion: Trans-arterial chemoembolization plus lenvatinib and camrelizumab shows good results incontrolling tumour progression and prolonging median OS in patients with advanced HCC.

9.
Biochem J ; 477(6): 1159-1178, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32065231

RESUMO

Overexpression of S100P promotes breast cancer metastasis in animals and elevated levels in primary breast cancers are associated with poor patient outcomes. S100P can differentially interact with nonmuscle myosin (NM) isoforms (IIA > IIC > IIB) leading to the redistribution of actomyosin filaments to enhance cell migration. Using COS-7 cells which do not naturally express NMIIA, S100P is now shown to interact directly with α,ß-tubulin in vitro and in vivo with an equilibrium Kd of 2-3 × 10-7 M. The overexpressed S100P is located mainly in nuclei and microtubule organising centres (MTOC) and it significantly reduces their number, slows down tubulin polymerisation and enhances cell migration in S100P-induced COS-7 or HeLa cells. It fails, however, to significantly reduce cell adhesion, in contrast with NMIIA-containing S100P-inducible HeLa cells. When taxol is used to stabilise MTs or colchicine to dissociate MTs, S100P's stimulation of migration is abolished. Affinity-chromatography of tryptic digests of α and ß-tubulin on S100P-bound beads identifies multiple S100P-binding sites consistent with S100P binding to all four half molecules in gel-overlay assays. When screened by NMR and ITC for interacting with S100P, four chemically synthesised peptides show interactions with low micromolar dissociation constants. The two highest affinity peptides significantly inhibit binding of S100P to α,ß-tubulin and, when tagged for cellular entry, also inhibit S100P-induced reduction in tubulin polymerisation and S100P-enhancement of COS-7 or HeLa cell migration. A third peptide incapable of interacting with S100P also fails in this respect. Thus S100P can interact directly with two different cytoskeletal filaments to independently enhance cell migration, the most important step in the metastatic cascade.


Assuntos
Proteínas de Ligação ao Cálcio/biossíntese , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Proteínas de Neoplasias/biossíntese , Tubulina (Proteína)/biossíntese , Animais , Células COS , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/genética , Chlorocebus aethiops , Células HeLa , Humanos , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Ligação Proteica/fisiologia , Estrutura Secundária de Proteína , Tubulina (Proteína)/química , Tubulina (Proteína)/genética
10.
World J Gastroenterol ; 26(47): 7513-7527, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33384551

RESUMO

BACKGROUND: Liver fibrosis progressing to liver cirrhosis and hepatic carcinoma is very common and causes more than one million deaths annually. Fibrosis develops from recurrent liver injury but the molecular mechanisms are not fully understood. Recently, the TLR4-MyD88 signaling pathway has been reported to contribute to fibrosis. Extracellular histones are ligands of TLR4 but their roles in liver fibrosis have not been investigated. AIM: To investigate the roles and potential mechanisms of extracellular histones in liver fibrosis. METHODS: In vitro, LX2 human hepatic stellate cells (HSCs) were treated with histones in the presence or absence of non-anticoagulant heparin (NAHP) for neutralizing histones or TLR4-blocking antibody. The resultant cellular expression of collagen I was detected using western blotting and immunofluorescent staining. In vivo, the CCl4-induced liver fibrosis model was generated in male 6-week-old ICR mice and in TLR4 or MyD88 knockout and parental mice. Circulating histones were detected and the effect of NAHP was evaluated. RESULTS: Extracellular histones strongly stimulated LX2 cells to produce collagen I. Histone-enhanced collagen expression was significantly reduced by NAHP and TLR4-blocking antibody. In CCl4-treated wild type mice, circulating histones were dramatically increased and maintained high levels during the duration of fibrosis-induction. Injection of NAHP not only reduced alanine aminotransferase and liver injury scores, but also significantly reduced fibrogenesis. Since the TLR4-blocking antibody reduced histone-enhanced collagen I production in HSC, the CCl4 model with TLR4 and MyD88 knockout mice was used to demonstrate the roles of the TLR4-MyD88 signaling pathway in CCl4-induced liver fibrosis. The levels of liver fibrosis were indeed significantly reduced in knockout mice compared to wild type parental mice. CONCLUSION: Extracellular histones potentially enhance fibrogenesis via the TLR4-MyD88 signaling pathway and NAHP has therapeutic potential by detoxifying extracellular histones.


Assuntos
Histonas , Receptor 4 Toll-Like , Animais , Tetracloreto de Carbono/toxicidade , Células Estreladas do Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fator 88 de Diferenciação Mieloide/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(2): 557-562, 2018 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29665932

RESUMO

OBJECTIVE: To explore the effects of blocking TCR-CD3 and B7-CD28 signals on immune function of mice with chronic GVHD by using TJU103 and CTLA4-Ig. METHODS: On the basis of foregoing murine model of chronic GVHD, according to interference modes after infusion 6×107 spleen cells of donor mice, the recipients were divided into 5 groups: blank control, cGVHD, TJU103 interference, CTLA4-Ig interference and TJU103+CTLA4-Ig interference groups. The score of clinical manifestation and tissue histopathology were used to evaluate the effects of all the interferences on chronic GVHD. RESULTS: TJU103 and CTLA4-Ig could not influence the formation of the mouse chimera. The analysis of Kaplan survival curve of mice with chronic GVHD showed that the CTLA4-Ig and TJU103+CTLA4-Ig reduced the incidence of chronic GVHD, the TJU103 could delay the occurrence of chronic GVHD, but all the interference factors could not change the severity of chronic GVHD. CONCLUSION: TJU103 can delay the onset time of chronic GVHD, and the CTLA4-Ig can reduce the incidences of cGVHD, the combining use of TJU103 and CTLA4-Ig can significantly reduce the incidence of chronic GVHD, but can not change the severity of chronic GVHD.


Assuntos
Doença Enxerto-Hospedeiro/prevenção & controle , Linfócitos T , Abatacepte , Animais , Células Apresentadoras de Antígenos , Antígenos CD , Antígenos de Diferenciação , Antígeno CTLA-4 , Doença Crônica , Imunoconjugados , Camundongos , Camundongos Endogâmicos C57BL
12.
Am J Transl Res ; 8(5): 2331-42, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27347341

RESUMO

BACKGROUND: Human adenovirus type 7 (HAdV7) is globally attracting great concern as its high morbidity and severity in respiratory diseases, especially in Asia. OBJECTIVE: To investigate the clinical and epidemiologic characteristics of HAdV7 infection outbreak in East China. METHODS: The clinical samples were collected from the patients of an ARD outbreak in East Chinafor the detection of causative pathogens by multiplex PCR. The molecular type of human adenovirus isolates were identified by sequencing and homologous comparison based on their hexon genes. The spatiotemporal dynamics of global HAdV7 was investigated using the phylogenetic and phylogeographic analyses. Total 67 referenced HAdV7 hexon sequences (>800 bp) from GenBank were selected for constructing the maximum likelihood tree by MEGA 5.1.0, grouped according to the tree topology for the further migration analysis by PAUP* 4.0 and MigraPhyla 1.0 b to understand the transmission patterns of HAdV7 in global epidemics. RESULTS: The results showed HAdV7 as the causative pathogen in this outbreak, and the outbreak strains had the hexon sequences highly identical with the isolates in Shaanxi (2012). The origin of HAdV7 was inferred as California, meanwhile a total of 21 migration routes were acquired. HAdV7 in this outbreak was statistically proven dispersed from Shaanxi province (2012). CONCLUSIONS: The analyses of epidemiology and transmission pattern of HAdV7 would not only enrich the molecular biological basic database but also provide theoretical basis for HAdV7 prevention and control strategy.

13.
Stroke ; 46(7): 1938-46, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26045601

RESUMO

BACKGROUND AND PURPOSE: An immature vascular phenotype in diabetes mellitus may cause more severe vascular damage and poorer functional outcomes after stroke, and it would be feasible to repair damaged functional vessels using endothelial progenitor cell (EPC) transplantation. However, high glucose induces p38 mitogen-activated protein kinase activation, which can accelerate the senescence and apoptosis of EPCs. The aim of this study was to investigate the combined effects of EPC transplantation and p38 mitogen-activated protein kinase inhibitor administration on diabetic stroke outcomes. METHODS: Bone marrow-derived EPCs were injected intra-arterially into db/db mice after ischemic stroke induction. RWJ 67657 (RWJ), a p38 mitogen-activated protein kinase inhibitor, was administered orally for 7 consecutive days, with the first dose given 30 minutes before stroke induction. Functional outcome was determined at days 0, 1, 7, 14, and 21. Angiogenesis, neurogenesis, infarct volume, and Western blotting assays were performed on day 7, and white matter remodeling was determined on day 14. RESULTS: Neither EPC transplantation nor RWJ administration alone significantly improved diabetic stroke outcome although RWJ displayed a potent anti-inflammatory effect. By both improving the functioning of EPCs and reducing inflammation, EPC transplantation plus RWJ administration in vivo synergistically promoted angiogenesis and neurogenesis after diabetic stroke. In addition, the white matter remodeling, behavioral scores, and expressions of vascular endothelial growth factor and brain-derived neurotrophic factor were significantly increased in diabetic mice treated with both EPCs and RWJ. CONCLUSIONS: The combination of EPC transplantation and RWJ administration accelerated recovery from diabetic stroke, which might have been caused by increased levels of proangiogenic and neurotrophic factors.


Assuntos
Isquemia Encefálica/terapia , Diabetes Mellitus Experimental/terapia , Células Progenitoras Endoteliais/transplante , Imidazóis/administração & dosagem , Piridinas/administração & dosagem , Transplante de Células-Tronco/métodos , Acidente Vascular Cerebral/terapia , Animais , Isquemia Encefálica/patologia , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Masculino , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Acidente Vascular Cerebral/patologia , Resultado do Tratamento
14.
Cancer Lett ; 361(1): 57-66, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25727320

RESUMO

Heparanase (HPA) is an endoglucuronidase that can promote the shedding of associated cytokines in several types of tumors. However, little is known about what controls the expression of HPA or its role in gastric cancer. In this study, we report for the first time that HGF regulates HPA expression to promote gastric cancer metastasis. In this study, HGF and HPA were found to be significantly expressed in 58 gastric cancer patients. High expression of both HGF and HPA was positively associated with TNM stage, invasion depth and poor prognosis. In MKN74 cells, exogenous HGF significantly increased HPA expression at both the mRNA and protein levels. Further study revealed that HGF first activated PI3K/Akt signaling. NF-κB signaling was activated downstream of PI3K/Akt and promoted HPA expression. However, when c-met, PI3K/Akt or NF-κB signal inhibitors were used, HPA expression was significantly decreased. All of these results indicate that HGF regulates HPA expression by PI3K/Akt and downstream NF-κB signaling. Using bioinformatics and the ChIP assay, p65 was observed to bind to the HPA promoter. Furthermore, HGF significantly induced tumor cell migration, whereas treatment with an NF-κB inhibitor decreased migration. Moreover, when HPA was overexpressed in MKN74 cells, migration was significantly enhanced, and the HGF concentration was increased. However, when HPA was down-regulated in MKN45 cells, migration and HGF levels decreased. Together, these results demonstrate that HGF/c-met can activate PI3K/Akt and downstream NF-κB signaling to promote HPA expression and subsequent tumor metastasis.


Assuntos
Movimento Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucuronidase/genética , Fator de Crescimento de Hepatócito/farmacologia , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/secundário , Western Blotting , Proliferação de Células/efeitos dos fármacos , Imunoprecipitação da Cromatina , Feminino , Mucosa Gástrica/metabolismo , Glucuronidase/metabolismo , Humanos , Luciferases/metabolismo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , NF-kappa B/genética , Estadiamento de Neoplasias , Fosfatidilinositol 3-Quinases/genética , Prognóstico , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-akt/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Estômago/efeitos dos fármacos , Estômago/patologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Taxa de Sobrevida , Ativação Transcricional/efeitos dos fármacos , Células Tumorais Cultivadas , Regulação para Cima , Cicatrização/efeitos dos fármacos
15.
PLoS One ; 10(12): e0145988, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26720630

RESUMO

OBJECTIVE: Damage to intestinal epithelial tight junctions plays an important role in sepsis. Recently we found that Carbon Monoxide-Releasing Molecule-2 (CORM-2) is able to protect LPS-induced intestinal epithelial tight junction damage and in this study we will investigate if CORM-2 could protect intestinal epithelial tight junctions in the rat cecal ligation and puncture (CLP) model. MATERIALS AND METHODS: The CLP model was generated using male Sprague-Dawley (SD) rats according to standard procedure and treated with CORM-2 or inactive CORM-2 (iCORM-2), 8 mg/kg, i.v. immediately after CLP induction and euthanized after 24h or 72h (for mortality rate only). Morphological changes were investigated using both transmission electron and confocal microscopy. The levels of important TJ proteins and phosphorylation of myosin light chain (MLC) were examined using Western blotting. Cytokines, IL-1ß and TNF-α were measured using ELISA kits. The overall intestinal epithelial permeability was evaluated using FD-4 as a marker. RESULTS: CORM-2, but not iCORM-2, significantly reduced sepsis-induced damage of intestinal mucosa (including TJ disruption), TJ protein reduction (including zonula occludens-l (ZO-1), claudin-1 and occludin), MLC phosphorylation and proinflammatory cytokine release. The overall outcomes showed that CORM-2 suppressed sepsis-induced intestinal epithelial permeability changes and reduced mortality rate of those septic rats. CONCLUSIONS: Our data strongly suggest that CORM-2 could be a potential therapeutic reagent for sepsis by suppressing inflammation, restoring intestinal epithelial barrier and reducing mortality.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Compostos Organometálicos/farmacologia , Sepse/metabolismo , Junções Íntimas/efeitos dos fármacos , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Interleucina-6/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/ultraestrutura , Cadeias Leves de Miosina/metabolismo , Permeabilidade/efeitos dos fármacos , Fosforilação , Ratos , Sepse/tratamento farmacológico , Sepse/mortalidade , Sepse/patologia , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/ultraestrutura , Fator de Necrose Tumoral alfa/metabolismo
16.
PLoS One ; 9(8): e104032, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25101775

RESUMO

OBJECTIVE: To investigate the protective effects and mechanisms of carbon monoxide-releasing molecule-2 (CORM-2) on barrier function of intestinal epithelial cells. MATERIALS AND METHODS: After pre-incubation with CORM-2 for 1 hour, cultured intestinal epithelial IEC-6 cells were stimulated with 50 µg/ml lipopolysaccharides (LPS). Cytokines levels in culture medium were detected using ELISA kits. Trans-epithelial electrical resistance (TER) of IEC-6 cell monolayers in Transwells were measured with a Millipore electric resistance system (ERS-2; Millipore) and calculated as Ω/cm2 at different time points after LPS treatment. The permeability changes were also measured using FITC-dextran. The levels of tight junction (TJ) proteins (occludin and ZO-1) and myosin light chain (MLC) phosphorylation were detected using Western blotting with specific antibodies. The subsequent structural changes of TJ were visualized using transmission electron microscopy (TEM). RESULTS: CORM-2 significantly reduced LPS-induced secretion of TNF-α and IL-1ß. The LPS-induced decrease of TER and increase of permeability to FITC-dextran were inhibited by CORM-2 in a concentration dependent manner (P<0.05). LPS-induced reduction of tight junction proteins and increase of MLC phosphorylation were also attenuated. In LPS-treated cells, TEM showed diminished electron-dense material and interruption of TJ and desmosomes between the apical lateral margins of adjoining cells, which were prevented by CORM-2 treatment. CONCLUSIONS: The present study demonstrates that CORM-2, as a novel CO-releasing molecule, has ability to protect the barrier function of LPS-stimulated intestinal epithelial cells. Inhibition of inflammatory cytokines release, restoration of TJ proteins and suppression of MLC phosphorylation are among the protective effects of CORM-2.


Assuntos
Monóxido de Carbono/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Substâncias Protetoras/farmacologia , Animais , Células Cultivadas , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/farmacologia , Microscopia Eletrônica de Transmissão , Ratos , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/ultraestrutura
17.
J Immunol ; 191(5): 2495-502, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23894199

RESUMO

C-reactive protein (CRP) is an acute-phase protein that plays an important defensive role in innate immunity against bacterial infection, but it is also upregulated in many noninfectious diseases. The generic function of this highly conserved molecule in diseases that range from infection, inflammation, trauma, and malignancy is not well understood. In this article, we demonstrate that CRP defends the human body against the toxicity of histones released into the circulation after extensive cell death. In vitro, CRP significantly alleviates histone-induced endothelial cell damage, permeability increase, and platelet aggregation. In vivo, CRP rescues mice challenged with lethal doses of histones by inhibiting endothelial damage, vascular permeability, and coagulation activation, as reflected by significant reductions in lung edema, hemorrhage, and thrombosis. In patients, elevation of CRP significantly increases the capacity to neutralize extracellular histones in the circulation. We have also confirmed that CRP interacts with individual histones in vitro and forms CRP-histone complexes in serum from patients with both elevated CRP and histones. CRP is able to compete with phospholipid-containing liposomes for the binding to histones. This explains how CRP prevents histones from integrating into cell membranes, which would otherwise induce calcium influx as the major mechanism of cytotoxicity caused by extracellular histones. Because histone elevation occurs in the acute phase of numerous critical illnesses associated with extensive cell death, CRP detoxification of circulating histones would be a generic host defense mechanism in humans.


Assuntos
Proteína C-Reativa/metabolismo , Proteína C-Reativa/toxicidade , Histonas/metabolismo , Animais , Permeabilidade Capilar/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Patch-Clamp
18.
J Biol Chem ; 287(19): 15330-44, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22399300

RESUMO

S100 proteins promote cancer cell migration and metastasis. To investigate their roles in the process of migration we have constructed inducible systems for S100P in rat mammary and human HeLa cells that show a linear relationship between its intracellular levels and cell migration. S100P, like S100A4, differentially interacts with the isoforms of nonmuscle myosin II (NMIIA, K(d) = 0.5 µM; IIB, K(d) = 8 µM; IIC, K(d) = 1.0 µM). Accordingly, S100P dissociates NMIIA and IIC filaments but not IIB in vitro. NMIIA knockdown increases migration in non-induced cells and there is no further increase upon induction of S100P, whereas NMIIB knockdown reduces cell migration whether or not S100P is induced. NMIIC knockdown does not affect S100P-enhanced cell migration. Further study shows that NMIIA physically interacts with S100P in living cells. In the cytoplasm, S100P occurs in discrete nodules along NMIIA-containing filaments. Induction of S100P causes more peripheral distribution of NMIIA filaments. This change is paralleled by a significant drop in vinculin-containing, actin-terminating focal adhesion sites (FAS) per cell. The induction of S100P, consequently, causes significant reduction in cellular adhesion. Addition of a focal adhesion kinase (FAK) inhibitor reduces disassembly of FAS and thereby suppresses S100P-enhanced cell migration. In conclusion, this work has demonstrated a mechanism whereby the S100P-induced dissociation of NMIIA filaments leads to a weakening of FAS, reduced cell adhesion, and enhanced cell migration, the first major step in the metastatic cascade.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Movimento Celular/fisiologia , Adesões Focais/metabolismo , Proteínas de Neoplasias/metabolismo , Miosina não Muscular Tipo IIA/metabolismo , Citoesqueleto de Actina/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação/genética , Western Blotting , Proteínas de Ligação ao Cálcio/genética , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Doxiciclina/farmacologia , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Adesões Focais/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Cinética , Microscopia Confocal , Dados de Sequência Molecular , Proteínas de Neoplasias/genética , Miosina não Muscular Tipo IIA/genética , Ligação Proteica , Interferência de RNA , Homologia de Sequência de Aminoácidos , Transfecção
19.
Cancer Res ; 70(7): 2585-94, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20233877

RESUMO

Advances in medical imaging techniques, such as ultrasound, computed tomography, magnetic resonance imaging, and positron emission tomography, have made great progress in detecting tumors. However, these imaging techniques are unable to differentiate malignant tumors from benign ones. Recently developed optical imaging of tumors in small animals provides a useful method to distinguish malignant tumors from their surrounding normal tissues. Human telomerase reverse transcriptase (hTERT) is normally inactivated in most somatic cells, whereas it is commonly reactivated in many cancer cells. In this study, we constructed a lentiviral vector that expresses green fluorescent protein (GFP) driven by an optimized hTERT promoter to create a noninvasive tumor-specific imaging methodology. The activity of this optimized hTERT promoter was found to be equal to the activity of SV40 and cytomegalovirus promoters. In vitro experiments showed that GFP was only expressed in telomerase-positive tumor cells infected with this lentivirus, whereas there was no GFP expression in telomerase-negative tumor cells or normal somatic cells. We also found that subcutaneous telomerase-positive tumors could be visualized 24 hours after an intratumoral injection with this lentivirus by using a charge-coupled device (CCD) camera. In contrast, telomerase-negative tumors could not be imaged after an intratumoral injection even for 30 days. These results suggest that infection with lentivirus containing this optimized hTERT promoter might be a useful diagnostic tool for the real-time visualization of macroscopically invisible tumor tissues using a highly sensitive CCD imaging system.


Assuntos
Vetores Genéticos/genética , Lentivirus/genética , Neoplasias/diagnóstico , Neoplasias/enzimologia , Telomerase/análise , Imagem Corporal Total/métodos , Animais , Western Blotting , Linhagem Celular Tumoral , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Células HeLa , Humanos , Imuno-Histoquímica , Luciferases/análise , Luciferases/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/genética , Neoplasias/patologia , Regiões Promotoras Genéticas , Telomerase/biossíntese , Telomerase/genética , Transfecção
20.
Cancer Immunol Immunother ; 59(7): 1041-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20182872

RESUMO

Heparanase is expressed in almost all advanced tumors, and therefore it may serve as a potential target for tumor therapy. Our previous study has shown that heparanase can serve as a potential universal tumor-associated antigen (TAA) for the immunotherapy of advanced tumors. Further study demonstrated that the HLA-A*0201-restricted Cytotoxic T lymphocytes (CTL) epitopes Hpa525 (PAFSYSFFV), Hpa277 (KMLKSFLKA) and Hpa405 (WLSLLFKKL) from human heparanase could induce a potent anti-tumor immune response in vitro. The present study was designed to investigate whether the above peptides could induce immune responses in mice. Our results demonstrated that the effectors from heparanase peptide-immunized mice could effectively lyse various tumor cells that were heparanase positive and HLA-A*0201 matched. We also found that these peptide-specific CTLs did not lyse autologous lymphocytes that had low heparanase activity. Further study revealed that Hpa525, Hpa277, and Hpa405 peptides increased the frequency of IFN-gamma-producing T cells as compared to a negative peptide. These results suggest that Hpa525, Hpa277, and Hpa405 peptides are novel HLA-A*0201-restricted CTL epitopes capable of inducing heparanase-specific CTLs in mice. Because heparanase is expressed in most advanced malignant tumors, Hpa525, Hpa277, and Hpa405 peptide-based vaccines may be useful for the immunotherapy of patients with advanced tumors.


Assuntos
Epitopos de Linfócito T/imunologia , Glucuronidase/imunologia , Neoplasias/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Linhagem Celular Tumoral , Citotoxicidade Imunológica/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Ensaio de Imunoadsorção Enzimática , Antígenos HLA-A/imunologia , Antígeno HLA-A2 , Células Hep G2 , Humanos , Imunização/métodos , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias/patologia , Peptídeos/imunologia , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/metabolismo
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