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1.
Sensors (Basel) ; 23(9)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37177724

RESUMO

The mobile node location method can find unknown nodes in real time and capture the movement trajectory of unknown nodes in time, which has attracted more and more attention from researchers. Due to their advantages of simplicity and efficiency, intelligent optimization algorithms are receiving increasing attention. Compared with other algorithms, the black hole algorithm has fewer parameters and a simple structure, which is more suitable for node location in wireless sensor networks. To address the problems of weak merit-seeking ability and slow convergence of the black hole algorithm, this paper proposed an opposition-based learning black hole (OBH) algorithm and utilized it to improve the accuracy of the mobile wireless sensor network (MWSN) localization. To verify the performance of the proposed algorithm, this paper tests it on the CEC2013 test function set. The results indicate that among the several algorithms tested, the OBH algorithm performed the best. In this paper, several optimization algorithms are applied to the Monte Carlo localization algorithm, and the experimental results show that the OBH algorithm can achieve the best optimization effect in advance.

2.
Hereditas ; 159(1): 14, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35184762

RESUMO

Sepsis is a life-threatening condition in which the immune response is directed towards the host tissues, causing organ failure. Since sepsis does not present with specific symptoms, its diagnosis is often delayed. The lack of diagnostic accuracy results in a non-specific diagnosis, and to date, a standard diagnostic test to detect sepsis in patients remains lacking. Therefore, it is vital to identify sepsis-related diagnostic genes. This study aimed to conduct an integrated analysis to assess the immune scores of samples from patients diagnosed with sepsis and normal samples, followed by weighted gene co-expression network analysis (WGCNA) to identify immune infiltration-related genes and potential transcriptome markers in sepsis. Furthermore, gene regulatory networks were established to screen diagnostic markers for sepsis based on the protein-protein interaction networks involving these immune infiltration-related genes. Moreover, we integrated WGCNA with the support vector machine (SVM) algorithm to build a diagnostic model for sepsis. Results showed that the immune score was significantly lower in the samples from patients with sepsis than in normal samples. A total of 328 and 333 genes were positively and negatively correlated with the immune score, respectively. Using the MCODE plugin in Cytoscape, we identified four modules, and through functional annotation, we found that these modules were related to the immune response. Gene Ontology functional enrichment analysis showed that the identified genes were associated with functions such as neutrophil degranulation, neutrophil activation in the immune response, neutrophil activation, and neutrophil-mediated immunity. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed the enrichment of pathways such as primary immunodeficiency, Th1- and Th2-cell differentiation, T-cell receptor signaling pathway, and natural killer cell-mediated cytotoxicity. Finally, we identified a four-gene signature, containing the hub genes LCK, CCL5, ITGAM, and MMP9, and established a model that could be used to diagnose patients with sepsis.


Assuntos
Sepse , Máquina de Vetores de Suporte , Algoritmos , Perfilação da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Humanos , Sepse/diagnóstico , Sepse/genética
3.
Clin Immunol ; 226: 108698, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33639275

RESUMO

T follicular helper (TFH) cells are a heterogeneous subset of immunocompetent T helper (TH) cells capable of augmenting B cell responses in lymphoid tissues. In transplantation, exposure to allogeneic tissue activates TFH cells increasing the risk of the emergence of de novo donor-specific HLA-antibodies (dnDSA). These can cause antibody-mediated rejection (AMR) and allograft loss. Follicular regulatory T (TFR) cells counteract TFH cell activity. Here, we investigated the implications of TFH and TFR cells on dnDSA formation after renal transplantation (RTX). Considering TFH cells to be CXCR5+ and IL-21+, we found by flow cytometry that patients with dnDSA produced IL-21 more abundantly compared to healthy volunteers. In in vitro alloreactivity assays, patients with dnDSA featured an enhanced alloreactive TH cell pool in response to donor-specific HLA antigens. Besides, longitudinal investigations suggested enhanced alloreactivity shortly after transplantation increasing the risk of dnDSA development. Taken together, in spite of continuous immunosuppression we report a strong IL-21 response in TFH cells and an expanded reservoir of donor-specific memory TH cells in patients with dnDSA. This warrants further investigations if aberrant TFH cell activation may precede the formation of dnDSA promoting AMR.


Assuntos
Anticorpos/imunologia , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Antígenos HLA/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adulto , Feminino , Humanos , Tolerância Imunológica/imunologia , Interleucinas/imunologia , Transplante de Rim , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Receptores CXCR5/imunologia
4.
J Biol Chem ; 294(13): 4815-4827, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30659097

RESUMO

Hepatitis B virus X protein (HBx) critically contributes to the development of hepatocellular carcinoma (HCC). However, the mechanisms by which HBx promotes HCC remain unclear. In the present study, using a combination of gene expression profiling and immunohistochemistry, we found higher levels of SH2 domain-containing 5 (SH2D5) in liver tissue from HBV-associated HCC (HBV-HCC) patients than in adjacent nontumor tissues. Moreover, HBV infection elevated SH2D5 levels, and we observed that HBx plays an important role in SH2D5 induction. We also found that HBx triggers SH2D5 expression through the NF-κB and c-Jun kinase pathways. Employing SH2D5 overexpression or knockdown, we further demonstrate that SH2D5 promotes HCC cell proliferation both in vitro and in vivo While investigating the mechanism of SH2D5-mediated stimulation of HCC cell proliferation, we noted that HBV induces SH2D5 binding to transketolase (TKT), a pentose phosphate pathway enzyme, thereby promoting an interaction between and signal transducer and activator of transcription 3 (STAT3). Furthermore, HBx stimulated STAT3 phosphorylation at Tyr-705 and promoted the activity and downstream signaling pathway of STAT3 via the SH2D5-TKT interaction. Taken together, our results suggest that SH2D5 is an HBV-induced protein capable of binding to TKT, leading to induction of HCC cell proliferation.


Assuntos
Carcinoma Hepatocelular/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Vírus da Hepatite B/metabolismo , Hepatite B/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Transativadores/metabolismo , Transcetolase/biossíntese , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Células Hep G2 , Hepatite B/genética , Hepatite B/patologia , Vírus da Hepatite B/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , NF-kappa B/genética , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Proteínas Adaptadoras da Sinalização Shc/genética , Transativadores/genética , Transcetolase/genética , Proteínas Virais Reguladoras e Acessórias
5.
Clin Immunol ; 208: 108258, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31499181

RESUMO

OBJECTIVES: Cytomegalovirus infection (CMVi) occurs frequently in transplant patients. Co-inhibitory molecules on CMV-specific T-cells (TCMV) in patients after lung transplantation were investigated. METHODS: 59 lung transplant patients were stratified according to anti-CMV serostatus at time of transplantation. The co-inhibitors Programmed-Death-Receptor-1 (PD1) and B-and-T-Lymphocyte-Attenuator (BTLA) were detected on TCMV by flow cytometry (FACS). RESULTS: TCMV were detectable in CMV sero-positive patients (R+) and in CMV sero-negative patients with a lung graft of a CMV sero-positive donor (D+/R-); in both cases, the frequency of TCMV was higher than in healthy controls (HC). PD-1 on TCMV was increased in D+/R+ and D+/R- patients as compared to HC. BTLA was significantly enhanced on TCMV of D+/R- patients vs. HC. R+ patients with CMV reactivation in the past had an increased fraction of BTLA+ TCMV. CONCLUSION: In conclusion, the expression pattern of co-inhibitory molecules on TCMV is altered in patients after lung transplantation.


Assuntos
Infecções por Citomegalovirus/imunologia , Hospedeiro Imunocomprometido/imunologia , Transplante de Pulmão , Linfócitos T/imunologia , Ativação Viral/imunologia , Antígeno B7-H1/biossíntese , Antígeno B7-H1/imunologia , Citomegalovirus/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores Imunológicos/biossíntese , Receptores Imunológicos/imunologia
6.
J Biol Chem ; 292(31): 12874-12884, 2017 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-28620049

RESUMO

The X-linked deubiquitinase USP9X has been implicated in multiple pathological disorders including malignancies and X-linked intellectual disability. However, its biological function and substrate repertoire remain to be investigated. In this study, we utilized the tandem mass tag labeling assay to identify USP9X-regulated proteins and revealed that the expression of multiple genes is altered in USP9X-deficient cells. Interestingly, we showed that USP9X promotes stabilization of centrosome proteins PCM1 and CEP55 through its catalytic activity. Remarkably, we demonstrated that USP9X is physically associated and spatially co-localized with PCM1 and CEP55 in the centrosome, and we revealed that either PCM1 or CEP55 loss resulted in impairment of USP9X centrosome localization. Moreover, we showed that USP9X is required for centrosome duplication, and this effect is dependent on its catalytic activity and its N-terminal module, which is responsible for physical association of USP9X with PCM1 and CEP55. Collectively, our experiments identified USP9X as an integral component of the centrosome where it functions to stabilize PCM1 and CEP55 and promote centrosome biogenesis.


Assuntos
Autoantígenos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Centrossomo/enzimologia , Regulação da Expressão Gênica , Proteínas Nucleares/metabolismo , Ubiquitina Tiolesterase/metabolismo , Substituição de Aminoácidos , Autoantígenos/química , Autoantígenos/genética , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Centrossomo/metabolismo , Deleção de Genes , Humanos , Imunoprecipitação , Mutação , Proteínas Nucleares/química , Proteínas Nucleares/genética , Oligopeptídeos/genética , Oligopeptídeos/metabolismo , Biogênese de Organelas , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Domínios e Motivos de Interação entre Proteínas , Estabilidade Proteica , Transporte Proteico , Proteômica/métodos , Interferência de RNA , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Ubiquitina Tiolesterase/antagonistas & inibidores , Ubiquitina Tiolesterase/química , Ubiquitina Tiolesterase/genética
7.
Clin Immunol ; 188: 45-51, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29274388

RESUMO

OBJECTIVES: B-cells play a crucial role in the pathogenesis of lupus nephritis. Recently, a separate subset has been discovered characterized by expression of Granzyme B. The aim of this study is to investigate this subset in patients with systemic lupus erythematosus (SLE). METHODS: Isolated PBMCs of SLE-patients (n=30) and healthy controls (n=21) were in vitro stimulated with CPG, IgG+IgM and IL-21. Patients were sub-grouped in patients with and without biopsy proven lupus nephritis. B-cells were analyzed for intracellular Granzyme B expression by flow cytometry. RESULTS: The strongest stimulus for Granzyme B secretion of B-cells was IgG+IgM in presence of IL-21. SLE-patients had a significant decreased percentage of Granzyme B+ B-cells in particular SLE-patients with active disease and with lupus nephritis. CONCLUSIONS: The frequency of GrB+ producing B-cells is reduced in SLE patients. This may contribute to an imbalanced B-cell regulation towards effector B-cells which might promote the development of lupus nephritis.


Assuntos
Linfócitos B/efeitos dos fármacos , Granzimas/imunologia , Interleucinas/farmacologia , Lúpus Eritematoso Sistêmico/imunologia , Nefrite Lúpica/imunologia , Adulto , Antígenos CD19/imunologia , Antígenos CD19/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Cultivadas , Feminino , Granzimas/metabolismo , Humanos , Imunoglobulina G/imunologia , Imunoglobulina G/farmacologia , Imunoglobulina M/imunologia , Imunoglobulina M/farmacologia , Interleucinas/imunologia , Lúpus Eritematoso Sistêmico/metabolismo , Nefrite Lúpica/metabolismo , Masculino , Pessoa de Meia-Idade , Receptores de Interleucina-21/imunologia , Receptores de Interleucina-21/metabolismo
8.
Int J Mol Sci ; 19(12)2018 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-30544783

RESUMO

In kidney transplant recipients, the cytomegalovirus (CMV) is frequently causing infection/reactivation and can trigger allograft rejection. To assess the risk of reactivation, the cellular immune response against CMV is increasingly assessed by cellular in vitro methods, such as the interferon (IFN)-γ ELISpot. In the current study we compared the IFN-γ ELISpot with our newly established CMV-specific ELISpot assays determining IL-17A, IL-21, IL-22, granzyme B, and perforin and correlated the results with flow cytometric data and clinical parameters. In 77 kidney transplant recipients, the highest frequency was observed for CMV pp65-specific cells secreting IFN-γ, followed by cells secreting IL-21 (62.9 and 23.2 Δ spot forming cells/105 cells). We observed a positive correlation between the percentage of CMV-specific CD3+ CD4+ CD154+ cells and results of the CMV-specific IL-21 ELISpot (p = 0.002). Results of the CMV pp65-specific IL-21 ELISpot correlated negatively with kidney function (estimated glomerular filtration rate, p = 0.006) and were significantly higher in women (p = 0.005). IL-21, a cytokine involved in aging that is secreted by activated CD4+ T cells, may also impact on allograft function. Thus, the CMV-specific IL-21 ELISpot could become a new tool to assess if CMV seropositivity represents a hazard for the graft.


Assuntos
Citomegalovirus/metabolismo , ELISPOT/métodos , Interleucinas/metabolismo , Transplante de Rim , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Especificidade da Espécie , Transplante Homólogo , Adulto Jovem
9.
Clin Immunol ; 184: 48-53, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28461110

RESUMO

OBJECTIVES: A separate subset of Granzyme B (GrB) producing B-cells regulating T-cell mediated immunity has been identified. In the present study, we investigated the role of GrB+ B-cells in renal transplant patients (RTX). METHODS: 12 healthy controls (HC) and 26 RTX patients were enrolled. In addition, 19 healthy volunteers treated with cyclosporine A (CsA) were enrolled. GrB+ B-cells were determined via flow cytometry. RESULTS: RTX Patients showed a diminished fraction of GrB+ B-cells as compared to HC. CsA treatment of healthy volunteers had no impact on the development of GrB+ B-cells. RTX patients with a history of allograft rejection showed an increased frequency of GrB+ B-cells. RTX patients with at least one episode of CMV viremia tended to have lower GrB+ B-cells as compared to patients without viremic episodes. CONCLUSION: We demonstrate that treatment with CsA does not impair the development of GrB+ B-cells. GrB+ B-cells may have a dual role in renal transplantation as regulatory cells to maintain allospecific tolerance and as effector cells enhancing viral control.


Assuntos
Linfócitos B/metabolismo , Granzimas/metabolismo , Transplante de Rim , Corticosteroides/uso terapêutico , Idoso , Linfócitos B/efeitos dos fármacos , Estudos de Casos e Controles , Ciclosporina/farmacologia , Ciclosporina/uso terapêutico , Feminino , Rejeição de Enxerto/prevenção & controle , Granzimas/efeitos dos fármacos , Humanos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Interleucinas/farmacologia , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico , Tacrolimo/uso terapêutico
10.
World J Surg Oncol ; 14(1): 196, 2016 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-27464949

RESUMO

BACKGROUND: The treatment of hepatocellular carcinoma (HCC) is complicated and challenging because of the frequent presence of cirrhosis. Therefore, we propose a novel surgical approach to minimize the invasiveness and risk in patients with HCC, hypersplenism, and esophagogastric varices. METHODS: This was a retrospective study carried out in 25 patients with HCC and hypersplenism and who underwent simultaneous laparoscopic-guided radio-frequency ablation and laparoscopic splenectomy with endoscopic variceal ligation. Tumor size was restricted to a single nodule of <3 cm. Characteristics of the patients (cirrhosis etiology, liver function, tumor size, spleen size), surgery (complications, blood loss, time of stay), and follow-up (recurrence and survival) were examined. RESULTS: Mean operative time was 128 ± 18 min. Mean blood loss was 206 ± 57 mL. Length of stay was 7.0 ± 1.5 days. Mean total costs were 8064 USD. Cytopenia and thrombocytopenia recovered quickly after surgery. No procedure was converted to open surgery. Two patients showed worsening liver function after surgery, three patients showed worsening of ascites, and five patients suffered from portal vein thrombosis. The 1-year tumor-free survival was 78.8 %, and the 21-month tumor-free survival was 61.4 %. According to a literature review, these outcomes were comparable to those of simultaneous open hepatic resection and splenectomy. CONCLUSIONS: Laparoscopic-guided radio-frequency ablation with laparoscopic splenectomy and endoscopic variceal ligation could be an available technique for patients with HCC <3 cm, hypersplenism, and esophagogastric varices. This approach may help to minimize the surgical risks and results in a fast increase in platelet counts with an acceptable rate of complications.


Assuntos
Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/métodos , Neoplasias Hepáticas/cirurgia , Esplenectomia/métodos , Adulto , Idoso , Perda Sanguínea Cirúrgica , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/patologia , Ablação por Cateter/efeitos adversos , Intervalo Livre de Doença , Varizes Esofágicas e Gástricas/etiologia , Varizes Esofágicas e Gástricas/cirurgia , Feminino , Seguimentos , Humanos , Hiperesplenismo/cirurgia , Laparoscopia , Tempo de Internação , Ligadura , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/prevenção & controle , Recidiva Local de Neoplasia/patologia , Duração da Cirurgia , Contagem de Plaquetas , Estudos Retrospectivos , Esplenectomia/efeitos adversos , Resultado do Tratamento
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