Intracellular expression of IRF9 Stat fusion protein overcomes the defective Jak-Stat signaling and inhibits HCV RNA replication

Interferon alpha (IFN-α) binds to a cell surface receptor that activates the Jak-Stat signaling pathway. A critical component of this pathway is the translocation of interferon stimulated gene factor 3 (a complex of three proteins Stat1, Stat2 and IRF9) to the nucleus to activate antiviral genes. A stable sub-genomic replicon cell line resistant to IFN-α was developed in which the nuclear translocation of Stat1 and Stat2 proteins was prevented due to the lack of phosphorylation; whereas the nuclear translocation of IRF9 protein was not affected. In this study, we sought to overcome defective Jak-Stat signaling and to induce an antiviral state in the IFN-α resistant replicon cell line by developing a chimera IRF9 protein fused with the trans activating domain (TAD) of either a Stat1 (IRF9-S1C) or Stat2 (IRF9-S2C) protein. We show here that intracellular expression of fusion proteins using the plasmid constructs of either IRF9-S1C or IRF9-S2C, in the IFN-α resistant cells, resulted in an increase in Interferon Stimulated Response Element (ISRE) luciferase promoter activity and significantly induced HLA-1 surface expression. Moreover, we show that transient transfection of IRF9-S1C or IRF9-S2C plasmid constructs into IFN-α resistant replicon cells containing sub-genomic HCV1b and HCV2a viruses resulted in an inhibition of viral replication and viral protein expression independent of IFN-α treatment. The results of this study indicate that the recombinant fusion proteins of IRF9-S1C, IRF9-S2C alone, or in combination, have potent antiviral properties against the HCV in an IFN-α resistant cell line with a defective Jak-Stat signaling

Mechanism of HCV's resistance to IFN-α in cell culture involves expression of functional IFN-α receptor 1

The mechanisms underlying the Hepatitis C virus (HCV) resistance to interferon alpha (IFN-α) are not fully understood. We used IFN-α resistant HCV replicon cell lines and an infectious HCV cell culture system to elucidate the mechanisms of IFN-α resistance in cell culture. The IFN-α resistance mechanism of the replicon cells were addressed by a complementation study that utilized the full-length plasmid clones of IFN-α receptor 1 (IFNAR1), IFN-α receptor 2 (IFNAR2), Jak1, Tyk2, Stat1, Stat2 and the ISRE- luciferase reporter plasmid. We demonstrated that the expression of the full-length IFNAR1 clone alone restored the defective Jak-Stat signaling as well as Stat1, Stat2 and Stat3 phosphorylation, nuclear translocation and antiviral response against HCV in all IFN-α resistant cell lines (R-15, R-17 and R-24) used in this study. Moreover RT-PCR, Southern blotting and DNA sequence analysis revealed that the cells from both R-15 and R-24 series of IFN-α resistant cells have 58 amino acid deletions in the extracellular sub domain 1 (SD1) of IFNAR1. In addition, cells from the R-17 series have 50 amino acids deletion in the sub domain 4 (SD4) of IFNAR1 protein leading to impaired activation of Tyk2 kinase. Using an infectious HCV cell culture model we show here that viral replication in the infected Huh-7 cells is relatively resistant to exogenous IFN-α. HCV infection itself induces defective Jak-Stat signaling and impairs Stat1 and Stat2 phosphorylation by down regulation of the cell surface expression of IFNAR1 through the endoplasmic reticulum (ER) stress mechanisms. The results of this study suggest that expression of cell surface IFNAR1 is critical for the response of HCV to exogenous IFN-α

Dentinal Dysplasia Type I: A Case Report with a 6-Year Followup

Introduction. Dentin dysplasia is a rare disturbance of dentin formation characterized by normal enamel but atypical dentin formation with abnormal pulpal morphology that is inherited as an autosomal pulpal morphology. Case Presentation. A 7-year-old female who had problems in chewing function was referred to Oral and Maxillofacial Surgery Department at the Faculty of Dentistry in Ondokuz Mayıs University. In the radiographic examination, it was determined that some of the unerupted permanent teeth of the patient had short, blunted, and malformed roots with obliterated pulp chambers, although the bone below the teeth showed well-defined margins. This unusual case of generalized short roots presents a case demonstrating both classic and atypical features of dentinal dysplasia type I (DDI) in the mixed and permanent dentitions. Conclusion. There are still many issues in the diagnosis and management of patients with dentin dysplasia. Early diagnosis, clinical and radiographic findings, as well as treatment of this condition and the initiation of effective preventive strategies may help prevent or delay loss of dentition

Youth suicide and hospital-presenting suicide attempts: Examination of risk factors for multiple suicide attempts in adolescence

Background: The suicide rate among adolescents around the world has increased rapidly. There are many risk factors for attempting suicide, but not all have been clarified yet. Therefore, it is very important to identify risk factors. This study evaluated adolescents with a history of suicide attempts and their association with chronic diseases. Besides, to check whether they attempted suicide multiple times. Other clinical features related to multiple suicide attempts were investigated. Method: This study used a multicentre, retrospective cross-sectional design; 253 adolescents admitted to emergency departments in 2019 for suicide attempts were evaluated. Results: Adolescents with chronic disease were at greater risk for both single and multiple suicide attempts and patients had a 6.14 times higher risk of multiple attempts (p = .013). The likelihood of multiple attempts did not differ according to the presence of somatic or psychiatric disease. Multiple attempters were more likely to poison themselves with their therapeutic drugs (p = .002). Conclusion: When adolescents with a chronic disease present to the emergency services after a single suicide attempt using their therapeutic drugs, families should be informed regarding the potential for further attempts

Sertraline Hepatotoxicity: Report of a Case and Review of the Literature

Sertraline is a commonly prescribed selective serotonin reuptake inhibitor drug. Hepatotoxicity caused by sertraline is rare. Asymptomatic elevations in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels have been rarely reported and shortly normalize after discontinuation of the agent. We present a case of severe drug-induced hepatitis in a patient receiving sertraline. To our knowledge, this is the seventh case in the medical literature as being associated with severe hepatotoxicity. Since it is extremely rare, we do not suggest a strict laboratory monitoring. However, sertraline should be discontinued in cases with symptoms implying hepatotoxicity and the patients should be informed of the potential of this side effect

Characteristics of Newly Diagnosed Hepatocellular Carcinoma Patients Across Turkey: Prospective Multicenter Observational 3K Registry Study

Aims: To evaluate patient profile for epidemiological and clinicopathological characteristics and potential risk/prognostic factors in newly diagnosed hepatocellular carcinoma (HCC) patients across Turkey. Methods: A total of 547 patients (mean (SD) age 62.6 (10.3) years, 81.9% were males) were included in this registry study. Data on patient characteristics, etiologies of HCC, laboratory values, and tumor characteristics and stages were recorded at study enrollment. Results: HBV infection (68.2%) was the leading etiology, followed by HCV infection (17.2%), HDV infection (5.5%), alcohol (6.4%), and NAFLD (3.5%), as the major etiologies. Considering that 51.6% of the patients had >5 cm HCC, 44% were Child-Pugh B/C and 57% were BCLC B-D, it appears that a significant group of HCC patients were diagnosed at advanced stages. Of 540 patients, 271 (50.2%) were referred or applied with the diagnosis of HCC. Patients with HCC at presentation had larger tumor size (median (min-max) 6.6 (0-30) vs. 4.8 (0-90) cm, P.001) and more advanced BCLC stage (Stage C-D in 40.8% vs. 26.4%, respectively, P=.005), compared to patients who were diagnosed during follow-up. Conclusions: Our findings revealed that HBV infection was the leading etiology and a moderate-to-advanced disease was evident in more than half of patients at the time of diagnosis. HCC patients diagnosed at follow-up had smaller tumor size and earlier BCLC stage.This study was supported by Bayer Turk. We thank Cagla Ayhan, MD and Sule Oktay, MD, PhD, from KAPPA Consultancy Training Research Ltd., Istanbul, who provided editorial support funded by Bayer Turk.Bayer Tur

Vitamin E has a dual effect of anti-inflammatory and antioxidant activities in acetic acid–induced ulcerative colitis in rats

Background: Increased free radical production, decreased antioxidant capacity and excessive inflammation are well-known features in the pathogenesis of inflammatory bowel disease. Vitamin E is a powerful antioxidant and a scavenger of hydroxyl radicals, and it has been shown to have anti-inflammatory activities in tissues. We investigated the effects of vitamin E on inflammatory activities using an acetic acid (AA)induced ulcerative colitis model in rats