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1.
Transplantation ; 108(3): 585-587, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38385338

RESUMO

Hepatic ischemia-reperfusion injury remains a significant challenge in liver transplantation potentially leading to delayed graft function, primary nonfunction, and sometimes rejection. Understanding the underlying mechanisms and implementing mitigation strategies are essential for improving transplant outcomes and patient survival. A recent study published by Dery et al shows that alternative splicing of carcinoembryonic antigen-related cell adhesion molecule 1 regulated by hypoxia inducible factor 1 alpha under stress enhances hepatic ischemia tolerance in mice and humans. The authors identified a direct binding of hypoxia inducible factor 1 alpha to the promoter region of polypyrimidine tract-binding protein 1 splicing enzyme, resulting in carcinoembryonic antigen-related cell adhesion molecule 1-short induction and improved posttransplant outcomes. This study has notably elucidated a potential biomarker pertaining to the quality of liver transplant donor grafts.


Assuntos
Proteína CEACAM1 , Traumatismo por Reperfusão , Animais , Humanos , Camundongos , Biomarcadores , Proteína CEACAM1/genética , Fator 1 Induzível por Hipóxia , Fígado/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Processamento Alternativo
2.
Heliyon ; 10(1): e23561, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38187339

RESUMO

Diabetes mellitus (DM) poses a significant global health burden, with hyperglycemia being a primary contributor to complications and high morbidity associated with this disorder. Existing glucose management strategies have shown suboptimal effectiveness, necessitating alternative approaches. In this study, we explored the role of high mobility group box 1 (HMGB1) in hyperglycemia, a protein implicated in initiating inflammation and strongly correlated with DM onset and progression. We hypothesized that HMGB1 knockdown will mitigate hyperglycemia severity and enhance glucose tolerance. To test this hypothesis, we utilized a novel inducible HMGB1 knockout (iHMGB1 KO) mouse model exhibiting systemic HMGB1 knockdown. Hyperglycemic phenotype was induced using low dose streptozotocin (STZ) injections, followed by longitudinal glucose measurements and oral glucose tolerance tests to evaluate the effect of HMGB1 knockdown on glucose metabolism. Our findings showed a substantial reduction in glucose levels and enhanced glucose tolerance in HMGB1 knockdown mice. Additionally, we performed RNA sequencing analyses, which identified potential alternations in genes and molecular pathways within the liver and skeletal muscle tissue that may account for the in vivo phenotypic changes observed in hyperglycemic mice following HMGB1 knockdown. In conclusion, our present study delivers the first direct evidence of a causal relationship between systemic HMGB1 knockdown and hyperglycemia in vivo, an association that had remained unexamined prior to this research. This discovery positions HMGB1 knockdown as a potentially efficacious therapeutic target for addressing hyperglycemia and, by extension, the DM epidemic. Furthermore, we have revealed potential underlying mechanisms, establishing the essential groundwork for subsequent in-depth mechanistic investigations focused on further elucidating and harnessing the promising therapeutic potential of HMGB1 in DM management.

3.
Cell Death Dis ; 15(1): 102, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291031

RESUMO

Early metastasis is the primary factor in the very poor prognosis of pancreatic ductal adenocarcinoma (PDAC), with liver metastasis being the most common form of distant metastasis in PDAC. To investigate the mechanism of PDAC liver metastasis, we found that PDAC cells can promote the formation of pre-metastatic niches (PMNs) through exosomes to facilitate liver metastasis in the early stage. In our study, hepatic stellate cells (HSCs) were treated with PDAC-derived exosomes (PDAC-exo), and the activation of HSCs was detected. A novel transfer RNA-derived fragment, the tRF-GluCTC-0005 was obtained by small RNA sequencing from serum exosomes of PDAC patients. Bioinformatics analysis and RNA pull-down assays revealed the interaction between WDR1 and tRF-GluCTC-0005. A KPC transgenic mouse model and an AAV-mediated sh-WDR1 mouse model were used to detect the mechanism of liver metastasis in vivo. Finally, the dual luciferase reporter assay, protein mutation truncation assay, Co-IP assay, and flow cytometry assay were used to explore the molecular mechanism in HSCs activation and PMNs formation. We found that the tRF-GluCTC-0005 in exosomes binds to the 3' untranslated region of the mRNA of the WDRl in HSCs and increases mRNA stability. The N-terminals of WDR1 bind to the YAP protein directly, inhibit YAP phosphorylation, and promote the expression of YAP transcription factors. The tRF-GluCTC-0005 in PDAC-exo significantly recruits myeloid-derived suppressor cells (MDSCs) in the liver, creating a PMNs immunosuppressive microenvironment and further advancing liver metastasis from PDAC. Our results suggest that the key of PDAC liver metastasis is the activation of HSCs through upregulation of WDR1 by tRF-GluCTC-0005 in exosomes, which mediates the infiltration of MDSCs to form PMNs.


Assuntos
Carcinoma Ductal Pancreático , Exossomos , Neoplasias Hepáticas , Neoplasias Pancreáticas , Humanos , Animais , Camundongos , Células Estreladas do Fígado/metabolismo , Exossomos/metabolismo , Linhagem Celular Tumoral , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Neoplasias Hepáticas/patologia , RNA de Transferência/metabolismo , Microambiente Tumoral
4.
J Pharm Pharmacol Res ; 7(4): 192-202, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37975061

RESUMO

Introduction: Metformin is the most prescribed medication in Diabetes Mellitus(DM). Metformin has shown to decrease mean platelet volume, with promising antiplatelet effects. High doses of Metformin have also been associated with hypercoagulation. We hypothesize that Metformin will protect DM mice from occlusive arterial thrombus formation by altering platelet activation and mitochondrial bioenergetics. Methods: DM was developed by low dose of Streptozotocin, non-DM (healthy) mice are controls. Either vehicle or Metformin was administered twice daily via oral gavage for 7-days. Ferric chloride (FeCl3) arterial thrombosis and tail bleeding time were performed. Whole blood aggregometry, platelet activation/adhesion and mitochondrial bioenergetics were evaluated. Results: Metformin decreased susceptibility of DM mice to arterial thrombosis. Platelet bioenergetics show DM mice have increased platelet mitochondrial respiration, but no differences were observed with Metformin treatment. In non-DM (healthy) mice, Metformin modulated ADP-dependent increase in platelet adhesion. Non-DM (healthy) mice, Metformin shortens bleeding time with faster thrombotic occlusion. Metformin also increased platelet mitochondrial maximal respiration and spare respiratory capacity uniquely in non-DM (healthy) mice. Conclusion: Metformin regulates platelet bioenergetics and ADP-mediated platelet function in DM mice which attenuates susceptibility to arterial thrombosis. Future studies will evaluate clinically relevant doses of Metformin that regulates thrombotic function in diabetic platelets.

5.
Res Sq ; 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37503167

RESUMO

Introduction: Metformin is the most prescribed medication in Diabetes Mellitus(DM). Metformin has shown to decrease mean platelet volume, with promising antiplatelet effects. High doses of Metformin have also been associated with hypercoagulation. We hypothesize that Metformin will protect DM mice from occlusive arterial thrombus formation by altering platelet activation and mitochondrial bioenergetics. Methods: DM was developed by low dose of Streptozotocin, healthy (non-DM) mice are controls. Either vehicle or Metformin was administered twice daily via oral gavage for 7-days. Ferric chloride (FeCl3) arterial thrombosis and tail bleeding time were performed. Whole blood aggregometry, platelet activation/adhesion and mitochondrial bioenergetics were evaluated. Results: Metformin decreased susceptibility of DM mice to arterial thrombosis. Platelet bioenergetics show DM mice have increased platelet mitochondrial respiration, but no differences were observed with Metformin treatment. In healthy mice, Metformin modulated ADP-dependent increase in platelet adhesion. In healthy mice, Metformin shortens bleeding time with faster thrombotic occlusion. Metformin also increased platelet mitochondrial maximal respiration and spare respiratory capacity uniquely in healthy mice. Conclusion: Metformin regulates platelet bioenergetics and ADP-mediated platelet function in DM mice which attenuates susceptibility to arterial thrombosis. Future studies will evaluate clinically relevant doses of Metformin that regulates thrombotic function in diabetic platelets.

6.
Metabolites ; 12(11)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36422261

RESUMO

Narcolepsy is a known auto-immune disease that presents mainly in the teenage years with irresistible sleep attacks. Patients with narcolepsy, especially NT1, have been found to have a high prevalence of obesity and other metabolic derangements. This narrative review aimed to address the relationship between narcolepsy and changes in weight and metabolic rate, and discuss potential mechanisms for weight gain and metabolic changes and future research agendas on this topic. This article will provide a balanced, up-to-date critical review of the current literature, and delineate areas for future research, in order to understand the pathophysiological metabolic changes in narcolepsy. Articles using predefined keywords were searched for in PubMed and Google Scholar databases, with predefined inclusion and exclusion criteria. Compared to controls, patients with narcolepsy are more likely to be obese and have higher BMIs and waist circumferences. According to recent research, weight gain in narcolepsy patients may be higher during the disease's outset. The precise mechanisms causing this weight gain remains unknown. The available information, albeit limited, does not support differences in basal or resting metabolic rates between patients with narcolepsy and controls, other than during the time of disease onset. The evidence supporting the role of orexin in weight gain in humans with narcolepsy is still controversial, in the literature. Furthermore, the available data did not show any appreciable alterations in the levels of CSF melanin-concentrating hormone, plasma and CSF leptin, or serum growth hormone, in relation to weight gain. Other mechanisms have been proposed, including a reduction in sympathetic tone, hormonal changes, changes in eating behavior and physical activity, and genetic predisposition. The association between increased body mass index and narcolepsy is well-recognized; however, the relationship between narcolepsy and other metabolic measures, such as body fat/muscle distribution and metabolic rate independent of BMI, is not well documented, and the available evidence is inconsistent. Future longitudinal studies with larger sample sizes are needed to assess BMR in patients with narcolepsy under a standard protocol at the outset of narcolepsy, with regular follow-up.

7.
Front Immunol ; 13: 887565, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35844608

RESUMO

The innate immune system plays an essential role in the response to sterile inflammation and its association with liver ischemia and reperfusion injury (IRI). Liver IRI often manifests during times of surgical stress such as cancer surgery or liver transplantation. Following the initiation of liver IRI, stressed hepatocytes release damage-associated molecular patterns (DAMPs) which promote the infiltration of innate immune cells which then initiate an inflammatory cascade and cytokine storm. Upon reperfusion, neutrophils are among the first cells that infiltrate the liver. Within the liver, neutrophils play an important role in fueling tissue damage and tumor progression by promoting the metastatic cascade through the formation of Neutrophil Extracellular Traps (NETs). NETs are composed of web-like DNA structures containing proteins that are released in response to inflammatory stimuli in the environment. Additionally, NETs can aid in mediating liver IRI, promoting tumor progression, and most recently, in mediating early graft rejection in liver transplantation. In this review we aim to summarize the current knowledge of innate immune cells, with a focus on neutrophils, and their role in mediating IRI in mouse and human diseases, including cancer and transplantation. Moreover, we will investigate the interaction of Neutrophils with varying subtypes of other cells. Furthermore, we will discuss the role and different treatment modalities in targeting Neutrophils and NETs to prevent IRI.


Assuntos
Armadilhas Extracelulares , Neoplasias , Traumatismo por Reperfusão , Animais , Armadilhas Extracelulares/metabolismo , Humanos , Fígado , Camundongos , Neoplasias/patologia , Neutrófilos , Traumatismo por Reperfusão/metabolismo
8.
Cells ; 11(14)2022 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-35883665

RESUMO

Ischemia reperfusion injury (IRI) is a major obstacle in liver resection and liver transplantation. The initial step of IRI is mediated through ischemia which promotes the production of reactive oxygen species in Kupffer cells. This furthermore promotes the activation of pro-inflammatory signaling cascades, including tumor necrosis factor-alpha, IL-6, interferon, inducible nitric oxide synthase, TLR9/nuclear-factor kappa B pathway, and the production of damage-associated molecular patterns (DAMPs), such as ATP, histone, high mobility group box 1 (HMGB1), urate, mitochondrial formyl peptides and S100 proteins. With ongoing cell death of hepatocytes during the ischemic phase, DAMPs are built up and released into the circulation upon reperfusion. This promotes a cytokines/chemokine storm that attracts neutrophils and other immune cells to the site of tissue injury. The effect of IRI is further aggravated by the release of cytokines and chemokines, such as epithelial neutrophil activating protein (CXCL5), KC (CXCL1) and MIP-2 (CXCL2), the complement proteins C3a and C5a, mitochondrial-derived formyl peptides, leukotriene B4 and neutrophil extracellular traps (NETs) from migrating neutrophils. These NETs can also activate platelets and form Neutrophil-platelet microthrombi to further worsen ischemia in the liver. In this review we aim to summarize the current knowledge of mediators that promote liver IRI, and we will discuss the role of neutrophils and neutrophil extracellular traps in mediating IRI.


Assuntos
Fígado , Traumatismo por Reperfusão , Quimiocinas/metabolismo , Citocinas/metabolismo , Humanos , Inflamação/metabolismo , Isquemia/patologia , Células de Kupffer/metabolismo , Fígado/metabolismo , Traumatismo por Reperfusão/metabolismo
9.
Can J Gastroenterol Hepatol ; 2021: 5212953, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34888264

RESUMO

Introduction: Hepatocellular carcinoma (HCC) accounts for approximately 90% of primary liver malignancies and is currently the fourth most common cause of cancer-related death worldwide. Due to varying underlying etiologies, the prognosis of HCC differs greatly among patients. It is important to develop ways to help stratify patients upon initial diagnosis to provide optimal treatment modalities and follow-up plans. The current study uses Artificial Neural Network (ANN) and Classification Tree Analysis (CTA) to create a gene signature score that can help predict survival in patients with HCC. Methods: The Cancer Genome Atlas (TCGA-LIHC) was analyzed for differentially expressed genes. Clinicopathological data were obtained from cBioPortal. ANN analysis of the 75 most significant genes predicting disease-free survival (DFS) was performed. Next, CTA results were used for creation of the scoring system. Cox regression was performed to identify the prognostic value of the scoring system. Results: 363 patients diagnosed with HCC were analyzed in this study. ANN provided 15 genes with normalized importance >50%. CTA resulted in a set of three genes (NRM, STAG3, and SNHG20). Patients were then divided in to 4 groups based on the CTA tree cutoff values. The Kaplan-Meier analysis showed significantly reduced DFS in groups 1, 2, and 3 (median DFS: 29.7 months, 16.1 months, and 11.7 months, p < 0.01) compared to group 0 (median not reached). Similar results were observed when overall survival (OS) was analyzed. On multivariate Cox regression, higher scores were associated with significantly shorter DFS (1 point: HR 2.57 (1.38-4.80), 2 points: 3.91 (2.11-7.24), and 3 points: 5.09 (2.70-9.58), p < 0.01). Conclusion: Long-term outcomes of patients with HCC can be predicted using a simplified scoring system based on tumor mRNA gene expression levels. This tool could assist clinicians and researchers in identifying patients at increased risks for recurrence to tailor specific treatment and follow-up strategies for individual patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Proteínas de Ciclo Celular , Estudos de Coortes , Humanos , Estimativa de Kaplan-Meier , Aprendizado de Máquina , Prognóstico , Fatores de Risco
10.
Cancers (Basel) ; 13(23)2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34885240

RESUMO

Metastasis is the leading cause of cancer related morbidity and mortality. The metastatic process involves several identifiable biological stages, including tumor cell dissemination, intravasation, and the extravasation of circulating cancer cells to facilitate colonization at a distant site. Immune cell infiltration and inflammation within the tumor microenvironment coincide with tumor progression and metastatic spread and are thought to be the key mediators of this complex process. Amongst many infiltrating cells, neutrophils have recently emerged as an important player in fueling tumor progression, both in animal models and cancer patients. The production of Neutrophil Extracellular Traps (NETs) is particularly important in the pathogenesis of the metastatic cascade. NETs are composed of web-like DNA structures with entangled proteins that are released in response to inflammatory cues in the environment. NETs play an important role in driving tumor progression both in experimental and clinical models. In this review, we aim to summarize the current advances in understanding the role of NETs in cancer, with a specific focus on their role in promoting premetastatic niche formation, interaction with circulating cancer cells, and in epithelial to mesenchymal transition during cancer metastasis. We will furthermore discuss the possible role and different treatment options for targeting NETs to prevent tumor progression.

11.
Front Immunol ; 12: 785222, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899751

RESUMO

While neutrophil extracellular traps (NETs) are important for directly promoting cancer growth, little is known about their impact on immune cells within the tumor microenvironment (TME). We hypothesize that NETs can directly interact with infiltrating T cells to promote an immunosuppressive TME. Herein, to induce a NET-rich TME, we performed liver Ischemia/Reperfusion (I/R) in an established cancer metastasis model or directly injected NETs in subcutaneous tumors. In this NET-rich TME, the majority of CD4+ and CD8+ tumor infiltrating lymphocytes expressed multiple inhibitory receptors, in addition these cells showed a functional and metabolic exhausted phenotype. Targeting of NETs in vivo by treating mice with DNAse lead to decreased tumor growth, decreased NET formation and higher levels of functioning T cells. In vitro, NETs contained the immunosuppressive ligand PD-L1 responsible for T cell exhaustion and dysfunction; an effect abrogated by using PD-L1 KO NETs or culturing NETs with PD-1 KO T cells. Furthermore, we found elevated levels of sPDL-1 and MPO-DNA, a NET marker, in the serum of patients undergoing surgery for colorectal liver metastases resection. Neutrophils isolated from patients after surgery were primed to form NETs and induced exhaustion and dysfunction of human CD4+ and CD8+ T cells. We next targeted PD-L1 in vivo by injecting a blocking antibody during liver I/R. A single dose of anti-PD-L1 during surgery lead to diminished tumors at 3 weeks and functional T cells in the TME. Our data thus reveal that NETs have the capability of suppressing T cell responses through metabolic and functional exhaustion and thereby promote tumor growth. Furthermore, targeting of PD-L1 containing NETs at time of surgery with DNAse or anti-PD-L1 lead to diminished tumor growth, which represents a novel and viable strategy for sustaining immune competence within the TME.


Assuntos
Adenocarcinoma/imunologia , Neoplasias Colorretais/imunologia , Armadilhas Extracelulares/imunologia , Neoplasias Hepáticas/imunologia , Linfócitos do Interstício Tumoral/imunologia , Neutrófilos/imunologia , Linfócitos T/imunologia , Evasão Tumoral , Microambiente Tumoral/imunologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/secundário , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Armadilhas Extracelulares/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/metabolismo , Fenótipo , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T/metabolismo
12.
Curr Pathobiol Rep ; 9(4): 107-117, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900401

RESUMO

Purpose of Review: COVID-19 has rapidly evolved into a global pandemic infecting over two hundred and forty-four million individuals to date. In addition to the respiratory sequelae and systemic infection that ensues, an alarming number of micro and macrovascular thrombotic complications have been observed. This review examines the current understanding of COVID-19-associated thrombotic complications, potential mechanisms, and pathobiological basis for thromboses development. Recent Findings: The endothelium plays a major role in the process due to direct and indirect injury. The immune system also contributes to a pro-thrombotic environment with immune cell dysregulation leading to excessive formation of cytokines, also called cytokine storm, and an eventual promotion of a hypercoagulable environment, known as immunothrombosis. Additionally, neutrophils play an important role by forming neutrophil extracellular traps, which are shown to be pro-thrombotic and further enhanced in COVID-19 patients. A disruption of the fibrinolysis system has also been observed. Summary: Multiple pathways likely contribute synergistically to form a pro-thrombotic milieu. A better understanding of these factors and the complex interplay between them will lead to the improvement of diagnostic and therapeutic interventions.

13.
Hepatology ; 73(6): 2494-2509, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32924145

RESUMO

BACKGROUND AND AIMS: Liver ischemia/reperfusion injury (IRI) induces local and systemic inflammation in which neutrophil extracellular traps (NETs) are major drivers. IRI markedly augments metastatic growth, which is consistent with the notion that the liver IRI can serve as a premetastatic niche. Exercise training (ExT) confers a sustainable protection, reducing IRI in some animal models, and has been associated with improved survival in patients with cancer; however, the impact of ExT on liver IRI or development of hepatic metastases is unknown. APPROACH AND RESULTS: Mice were randomized into exercise (ExT) and sedentary groups before liver IRI and tumor injection. Computerized dynamic network analysis of 20 inflammatory mediators was used to dissect the sequence of mediator interactions after ischemia/reperfusion (I/R) that induce injury. ExT mice showed a significant decrease in hepatic IRI and tissue necrosis. This coincided with disassembly of complex networks among inflammatory mediators seen in sedentary mice. Neutrophil infiltration and NET formation were decreased in the ExT group, which suppressed the expression of liver endothelial cell adhesion molecules. Concurrently, ExT mice revealed a distinct population of infiltrating macrophages expressing M2 phenotypic genes. In a metastatic model, fewer metastases were present 3 weeks after I/R in the ExT mice, a finding that correlated with a marked increase in tumor-suppressing T cells within the tumor microenvironment. CONCLUSIONS: ExT preconditioning mitigates the inflammatory response to liver IRI, protecting the liver from injury and metastases. In light of these findings, potential may exist for the reduction of liver premetastatic niches induced by liver IRI through the use of ExT as a nonpharmacologic therapy before curative surgical approaches.


Assuntos
Armadilhas Extracelulares/imunologia , Inflamação , Hepatopatias , Metástase Neoplásica , Infiltração de Neutrófilos/imunologia , Condicionamento Físico Animal/métodos , Traumatismo por Reperfusão , Animais , Proliferação de Células , Modelos Animais de Doenças , Imunidade , Inflamação/etiologia , Inflamação/imunologia , Inflamação/terapia , Hepatopatias/imunologia , Hepatopatias/patologia , Hepatopatias/terapia , Camundongos , Metástase Neoplásica/imunologia , Metástase Neoplásica/terapia , Fatores de Proteção , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/terapia , Resultado do Tratamento
14.
Med Biol Eng Comput ; 58(5): 1047-1068, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32144650

RESUMO

Sperm morphology, as an indicator of fertility, is a critical tool in semen analysis. In this study, a smartphone-based hybrid system that fully automates the sperm morphological analysis is introduced with the aim of eliminating unwanted human factors. Proposed hybrid system consists of two progressive steps: automatic segmentation of possible sperm shapes and classification of normal/ab-normal sperms. In the segmentation step, clustering techniques with/without group sparsity approach were tested to extract region of interests from the images. Subsequently, a novel publicly available morphological sperm image data set, whose labels were identified by experts as non-sperm, normal and abnormal sperm, was created as the ground truths of classification step. In the classification step, conventional and ensemble machine learning methods were applied to domain-specific features that were extracted by using wavelet transform and descriptors. Additionally, as an alternative to conventional features, three deep neural network architectures, which can extract high-level features from raw images after using statistical learning, were employed to increase the proposed method's performance. The results show that, for the conventional features, the highest classification accuracies were achieved as 80.5% and 83.8% by using the wavelet- and descriptor-based features that were fed to the Support Vector Machines respectively. On the other hand, the Mobile-Net, which is a very convenient network for smartphones, achieved 87% accuracy. In the light of obtained results, it is seen that a fully automatic hybrid system, which uses the group sparsity to enhance segmentation performance and the Mobile-Net to obtain high-level robust features, can be an effective mobile solution for the sperm morphology analysis problem. A fully automated hybrid human sperm detection and classification system based on mobile-net.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Análise do Sêmen/métodos , Smartphone , Espermatozoides , Adulto , Aprendizado Profundo , Humanos , Interpretação de Imagem Assistida por Computador/instrumentação , Masculino , Análise do Sêmen/instrumentação , Espermatozoides/classificação , Espermatozoides/fisiologia , Máquina de Vetores de Suporte , Análise de Ondaletas , Adulto Jovem
15.
J Vis Exp ; (150)2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31524857

RESUMO

Liver ischemia and reperfusion (I/R) injury, a common clinical challenge, remains an inevitable pathophysiological process that has been shown to induce multiple tissue and organ damage. Despite recent advances and therapeutic approaches, the overall morbidity has remained unsatisfactory especially in patients with underlying parenchymal abnormalities. In the context of aggressive cancer growth and metastasis, surgical I/R is suspected to be the promoter regulating tumor recurrence. This article aims to describe a clinically relevant murine model of liver I/R and colorectal liver metastasis. In doing so, we aim to assist other investigators in establishing and perfecting this model for their routine research practice to better understand the effects of liver I/R on promoting liver metastases.


Assuntos
Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Neoplasias Hepáticas/secundário , Traumatismo por Reperfusão , Animais , Masculino , Camundongos Endogâmicos C57BL
16.
Cancer Res ; 79(21): 5626-5639, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31519688

RESUMO

Neutrophil infiltration and neutrophil extracellular traps (NET) in solid cancers are associated with poorer prognosis, but the mechanisms are incompletely understood. We hypothesized that NETs enhance mitochondrial function in tumor cells, providing extra energy for accelerated growth. Metastatic colorectal cancer tissue showed increased intratumoral NETs and supranormal preoperative serum MPO-DNA, a NET marker. Higher MPO-DNA correlated with shorter survival. In mice, subcutaneous tumor implants and hepatic metastases grew slowly in PAD4-KO mice, genetically incapable of NETosis. In parallel experiments, human cancer cell lines grew slower in nu/nu mice treated with DNAse, which disassembles NETs. PAD4-KO tumors manifested decreased proliferation, increased apoptosis, and increased evidence of oxidative stress. PAD4-KO tumors had decreased mitochondrial density, mitochondrial DNA, a lesser degree of ATP production, along with significantly decreased mitochondrial biogenesis proteins PGC1α, TFAM, and NRF-1. In vitro, cancer cells treated with NETs upregulated mitochondrial biogenesis-associated genes, increased mitochondrial density, increased ATP production, enhanced the percentage of cancer cells with reduced mitochondrial membrane potential, and increased the oxygen consumption rate. Furthermore, NETs increased cancer cells' expression of fission and fusion-associated proteins, DRP-1 and MFN-2, and mitophagy-linked proteins, PINK1 and Parkin. All of which were decreased in PAD4-KO tumors. Mechanistically, neutrophil elastase released from NETs activated TLR4 on cancer cells, leading to PGC1α upregulation, increased mitochondrial biogenesis, and accelerated growth. Taken together, NETs can directly alter the metabolic programming of cancer cells to increase tumor growth. NETs represent a promising therapeutic target to halt cancer progression. SIGNIFICANCE: Neutrophils through the release of NETs facilitate the growth of stressed cancer cells by altering their bioenergetics, the inhibition of which induces cell death.


Assuntos
Proliferação de Células/fisiologia , Armadilhas Extracelulares/fisiologia , Homeostase/fisiologia , Mitocôndrias/fisiologia , Neutrófilos/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Biomarcadores/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , DNA Mitocondrial/metabolismo , Armadilhas Extracelulares/metabolismo , Células HCT116 , Humanos , Elastase de Leucócito/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Infiltração de Neutrófilos/fisiologia , Neutrófilos/metabolismo
17.
Saudi J Kidney Dis Transpl ; 30(1): 83-96, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30804270

RESUMO

Kidney transplantation is the most preferred treatment modality for patients with end-stage renal disease (ESRD). This study aims at understanding the awareness, attitudes, and beliefs among the medical and nonmedical students. The study population consisted of 500 medical students and 39 nonmedical controls, who were surveyed using a reliable questionnaire that examined their knowledge and attitudes. A 24-item self-administered questionnaire, which assessed the levels of knowledge, attitude regarding organ donation with dichotomous scale and demographic data were used. Of the 500 medical students who received the questionnaire, 376 (75.2%) with a mean age of 22.1 ± 2.5 years responded; 39% were male, 43.6% were Bahraini, and 32.2% were from Saudi Arabia, 51.3% were in Grades-5 and 6 and 58.8% resided in big cities. The medical students had a highly positive attitude and great willingness toward organ donation. Majority of them (75.3%) knew the treatment of ESRD, and 70.7% recognized correctly that kidney transplantation is the optimal treatment for ESRD. However, only 10.4% knew that it is performed in Bahrain since 1995. A total of 241 participants (64.3%) reported positive attitude toward living kidney donation and 71.8% expressed their agreement to donation after death. More than half (66.8%) believed that their religion permits organ donation, although 56.6% of the participants believed that there is a danger after donating a kidney. When compared to nonmedical students, there was no statistically significant difference in the attitudes toward living kidney donation (P = 0.823) or organ donation after death (P = 0.066).


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Transplante de Órgãos , Estudantes de Medicina/psicologia , Estudantes de Medicina/estatística & dados numéricos , Obtenção de Tecidos e Órgãos , Adulto , Barein/epidemiologia , Feminino , Humanos , Masculino , Inquéritos e Questionários , Adulto Jovem
18.
Cells ; 8(2)2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30695997

RESUMO

Autophagy is an evolutionary conserved intracellular mechanism which helps eukaryotic cells in maintaining their metabolic state to afford high-efficiency energy requirements. In the physiology of a normal liver and the pathogenesis of liver diseases, autophagy plays a crucial role. Autophagy has been found to be both upregulated and downregulated in different cancers providing the evidence that autophagy plays a dual role in suppressing and promoting cell survival. Hepatocellular carcinoma (HCC) is the most common primary liver cancer and the major leading cause of cancer mortality worldwide. In light of its high complexity and poor prognosis, it is essential to improve our understanding of autophagy's role in HCC. In this review, we summarize the dual mechanism of autophagy in the development of HCC and elucidate the currently used therapeutic strategies for anti-HCC therapy.


Assuntos
Autofagia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/terapia , Homeostase , Humanos , Fígado/patologia , Neoplasias Hepáticas/terapia , Metástase Neoplásica
19.
J Immunol ; 202(1): 268-277, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30504418

RESUMO

Hepatic ischemia reperfusion (I/R) is a clinically relevant model of acute sterile inflammation leading to a reverberating, self-sustaining inflammatory response with resultant necrosis. We hypothesized that computerized dynamic network analysis (DyNA) of 20 inflammatory mediators could help dissect the sequence of post-I/R mediator interactions that induce injury. Although the majority of measured inflammatory mediators become elevated in the first 24 h, we predicted that only a few would be secreted early in the process and serve as organizational centers of downstream intermediator complexity. In support of this hypothesis, DyNA inferred a central organizing role for IL-17A during the first 3 h of reperfusion. After that, DyNA revealed connections among almost all the inflammatory mediators, representing an ongoing cytokine storm. Blocking IL-17A immediately after reperfusion disassembled the inflammatory networks and protected the liver from injury. Disassembly of the networks was not achieved if IL-17A blockage was delayed two or more hours postreperfusion. Network disassembly was accompanied by decrease in neutrophil infiltration and neutrophil extracellular trap (NET) formation. By contrast, administration of recombinant IL-17A increased neutrophil infiltration, NET formation, and liver necrosis. The administration of DNase, a NET inhibitor, significantly reduced hepatic damage despite prior administration of IL-17A, and DNase also disassembled the inflammatory networks. In vitro, IL-17A was a potent promoter of NET formation. Therefore, computational analysis identified IL-17A's early, central organizing role in the rapid evolution of a network of inflammatory mediators that induce neutrophil infiltration and NET formation responsible for hepatic damage after liver I/R.


Assuntos
Biologia Computacional/métodos , Simulação por Computador , Armadilhas Extracelulares/imunologia , Interleucina-17/metabolismo , Fígado/patologia , Neutrófilos/imunologia , Traumatismo por Reperfusão/imunologia , Animais , Anticorpos Bloqueadores/administração & dosagem , Células Cultivadas , Desoxirribonucleases/metabolismo , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-17/imunologia , Fígado/cirurgia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Necrose , Infiltração de Neutrófilos , Mapas de Interação de Proteínas
20.
Hepatology ; 68(4): 1347-1360, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29631332

RESUMO

Nonalcoholic steatohepatitis (NASH) is a progressive, inflammatory form of fatty liver disease. It is the most rapidly rising risk factor for the development of hepatocellular carcinoma (HCC), which can arise in NASH with or without cirrhosis. The inflammatory signals promoting the progression of NASH to HCC remain largely unknown. The propensity of neutrophils to expel decondensed chromatin embedded with inflammatory proteins, known as neutrophil extracellular traps (NETs), has been shown to be important in chronic inflammatory conditions and in cancer progression. In this study, we asked whether NET formation occurs in NASH and contributes to the progression of HCC. We found elevated levels of a NET marker in serum of patients with NASH. In livers from STAM mice (NASH induced by neonatal streptozotocin and high-fat diet), early neutrophil infiltration and NET formation were seen, followed by an influx of monocyte-derived macrophages, production of inflammatory cytokines, and progression of HCC. Inhibiting NET formation, through treatment with deoxyribonuclease (DNase) or using mice knocked out for peptidyl arginine deaminase type IV (PAD4-/- ), did not affect the development of a fatty liver but altered the consequent pattern of liver inflammation, which ultimately resulted in decreased tumor growth. Mechanistically, we found that commonly elevated free fatty acids stimulate NET formation in vitro. CONCLUSION: Our findings implicate NETs in the protumorigenic inflammatory environment in NASH, suggesting that their elimination may reduce the progression of liver cancer in NASH. (Hepatology 2018).


Assuntos
Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica/patologia , Progressão da Doença , Armadilhas Extracelulares/metabolismo , Neutrófilos/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Animais , Biomarcadores/metabolismo , Biópsia por Agulha , Carcinoma Hepatocelular/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Prognóstico , Distribuição Aleatória , Medição de Risco
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