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1.
Approximately 75% to 80% of hepatocellular carcinomas (HCC) worldwide are attributed to chronic hepatitis B virus (HBV) and chronic hepatitis C virus (HCV) infection. Thus, effective prevention of HBV and HCV infection and progression from acute HBV and HCV infection to chronic hepatitis, cirrhosis and HCC might prevent as many as 450,000 deaths from HCC each year. The most effective approach to preventing HCC is to prevent HBV and HCV infection through vaccination. Indeed HBV vaccine is the first vaccine demonstrated to prevent cancers. However, a vaccine for HCV is not available and for persons who are chronically infected with HBV or HCV, antiviral therapy is the only option for preventing HCC. Direct evidence supporting a benefit of antiviral therapy on the prevention of HCC has been shown in a few randomized controlled trials. There is abundant evidence that antiviral therapy, in patients with long-term virological response, can improve liver histology, providing indirect support that antiviral therapy may prevent HCC by slowing progression of liver disease and possibly even reversing liver damage. Nevertheless, the risk of HCC remains in patients with chronic HBV or chronic HCV infection if treatment is initiated after cirrhosis is established. These data indicate that treatment might be of greater benefit if instituted earlier in the course of chronic hepatitis B or C. Safer, more effective, and more affordable antiviral therapies are needed for both hepatitis B and hepatitis C so more patients can benefit from treatment and more HCCs can be prevented.  相似文献   

2.
Hepatocellular carcinoma (HCC), one of the major malignant lethal tumours, is most prevalent in Asian patients with chronic hepatitis B virus (HBV) infection. Both viral and non‐viral factors contribute to the development of HCC. It is established that viral factors associated with HBV DNA level, HBV genotype, designated gene mutation, HBV DNA integration, HBx protein, hepatitis B surface antigen (HBsAg), hepatitis B core‐related antigen (HBcrAg) and HBV RNA are correlated with hepatocarcinogenesis. Before the introduction of antiviral therapy, viral factors once attracted more attention during the development of HCC. With the widespread use of antiviral therapy, predominantly nucleos(t)ide analogues (NAs), most patients with chronic hepatitis B (CHB) have achieved sustained viral control. The role of non‐viral factors, especially modifiable factors, is anticipated to be reinforced in the future. Herein, we reviewed the modifiable non‐viral risk factors of HBV‐related HCC, in the hope of providing substantial evidence for further development of novel precautionary measures for HCC. In addition, the therapeutic interventions for reducing the risk of HCC, like potential conventional pharmaceutical interventions and lifestyle modification are also discussed in this review. Future studies that would explore the specific mechanism of HBV‐related HCC development in patients with satisfactory viral control and related precision treatment are warranted.  相似文献   

3.
Hepatitis B virus (HBV) infection is a global health problem that causes a wide spectrum of liver disease, including acute or fulminant hepatitis, inactive carrier state, chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). The pathogenesis of hepatocyte damage associated with HBV is mainly through immune-mediated mechanisms. On the basis of the virus and host interactions, the natural history of HBV carriers who are infected in early life can be divided into four dynamic phases. The frequency, extent, and severity of hepatitis flares or acute exacerbation in the second immune clearance and/or fourth reactivation phase predict liver disease progression in HBV carriers. In the past decade, hepatitis B viral factors including serum HBV DNA level, genotype, and naturally occurring mutants predictive of clinical outcomes have been identified. The higher the serum HBV DNA level after the immune clearance phase, the higher the incidence of adverse outcomes over time. In addition, high viral load, genotype C, basal core promoter mutation, and pre-S deletion correlate with increased risk of cirrhosis and HCC development. As to the treatment of chronic hepatitis B, patients with high HBV DNA level and genotype C or D infection are shown to have a worse response to interferon therapy. In conclusion, serum HBV DNA level, genotype, and naturally occurring mutants are identified to influence liver disease progression and therapy of chronic hepatitis B. More investigations are needed to clarify the molecular mechanisms of the viral factors involved in the pathogenesis of each stage of liver disease and the response to antiviral treatments.  相似文献   

4.
Viral hepatitis due to chronic hepatitis B and C virus (HBV/HCV) infects more than 500 000 000 individuals worldwide. These chronic viral diseases are highly linked to the development of hepatocellular carcinoma (HCC), the fifth most common cause of cancer death worldwide. HCC is much more common in Asia and Africa than in the USA and Europe, although HCC is one of the few cancers with a rising incidence in the USA. There are 530 000 cases of HCC worldwide of which 82% are related to viral hepatitis. 316 000 cases of HCC are HBV-associated, 118 000 are HCV-associated. The most effective way to prevent HCC is to prevent viral infection through immunization. Currently there are effective vaccinesagainst hepatitis B and A, but not against HCV, the virus that accounts for most HCC in the USA. The published work supporting the use of antiviral therapy in preventing liver cancer is limited. Data supporting the use of antiviral therapy in preventing recurrence of HCC after initial anticancer approaches is even less available. Nevertheless, the weight of evidence suggests that treatment of HBV/HCV-related fibrosis will reduce the risk of developing HCC.  相似文献   

5.
Chronic hepatitis B virus(HBV) infection is a critical risk factor for the carcinogenesis and progression of hepatocellular carcinoma(HCC). It promotes HCC development by inducing liver fibrogenesis, genetic and epigenetic alterations, and the expression of active viral-coded proteins. Effective antiviral treatments inhibit the replication of HBV, reduce serum viral load and accelerate hepatitis B e antigen serum conversion. Timely initiation of antiviral treatment is not only essential for preventing the incidence of HCC in chronic hepatitis B patients, but also important for reducing HBV reactivation, improving liver function, reducing or delaying HCC recurrence, and prolonging overall survival of HBV-related HCC patients after curative and palliative therapies. The selection of antiviral drugs, monitoring of indicators such as HBV DNA and hepatitis B surface antigen, and timely rescue treatment when necessary, are essential in antiviral therapies for HBVrelated HCC.  相似文献   

6.
The outcome after curative resection for hepatocellular carcinoma (HCC) remains unsatisfactory due to the high recurrence rate after surgery. In patients with hepatitis B virus (HBV)-related HCC, which is the majority of patients with HCC in Asia, a high viral load is a strong risk factor for HCC recurrence. It is logical to believe that antiviral therapy may improve the post-operative outcome by promoting viral clearance and hepatocyte regeneration, as well as improving residual liver volume in HCC patients with hepatitis B. However, the effect of antiviral therapy on clinical outcomes after liver resection in patients with HBV-related HCC remains to be established. There are two main groups of antiviral treatment for HBV-oral nucleos(t)ide analogues and interferon. Interferon treatment reduces the overall incidence of HBV-related HCC in sustained responders. However, side effects may limit its long-term clinical application. Nucleos(t)ide analogues carry fewer side effects and are potent in terms of viral suppression when compared to interferon and are typically implemented for patients with more advanced liver diseases. They may also improve the outcome after curative resection for HBV-related HCC. There are increasing evidence to suggest that antiviral therapy could suppress HBV, decrease the perioperative reactivation of viral replication, reduce liver injury, preserve the liver function before and after operation, and may lower the risk of HCC recurrence. After all, antiviral therapy may improve the survival after liver resection by reducing recurrence and delaying the liver damage by the virus, resulting in a higher chance of receiving aggressive salvage therapy during HCC recurrence.  相似文献   

7.
Hepatocellular carcinoma (HCC) is one of the most frequent and fatal human cancers worldwide and its development and prognosis are intimately associated with chronic infection with hepatitis B virus (HBV). The identification of genetic mutations and molecular mechanisms that mediate HBV-induced tumorigenesis therefore holds promise for the development of potential biomarkers and targets for HCC prevention and therapy. The presence of HBV pre-S gene deletions in the blood and the expression of pre-S deleted proteins in the liver tissues of patients with chronic hepatitis B and HBV-related HCC have emerged as valuable biomarkers for higher incidence rates of HCC development and a higher risk of HCC recurrence after curative surgical resection, respectively. Moreover, pre-S deleted proteins are regarded as important oncoproteins that activate multiple signaling pathways to induce DNA damage and promote growth and proliferation in hepatocytes, leading to HCC development. The signaling molecules dysregulated by pre-S deleted proteins have also been validated as potential targets for the prevention of HCC development. In this review, we summarize the clinical and molecular implications of HBV pre-S gene deletions and pre-S deleted proteins in HCC development and recurrence and highlight their potential applications in HCC prevention and therapy.  相似文献   

8.
Chronic infection with viral hepatitis affects half a billion individuals worldwide and can lead to cirrhosis, cancer, and liver failure. Liver cancer is the third leading cause of cancer-associated mortality, of which hepatocellular carcinoma (HCC)represents 90%of all primary liver cancers. Solid tumors like HCC are complex and have heterogeneous tumor genomic profiles contributing to complexity in diagnosis and management. Chronic infection with hepatitis B virus (HBV),hepatitis delta virus (HDV), and hepatitis C virus (HCV) are the greatest etiological risk factors for HCC. Due to the significant role of chronic viral infection in HCC development, it is important to investigate direct (viral associated) and indirect (immune-associated) mechanisms involved in the pathogenesis of HCC. Common mechanisms used by HBV, HCV, and HDV that drive hepatocarcinogenesis include persistent liver inflammation with an impaired antiviral immune response, immune and viral protein-mediated oxidative stress, and deregulation of cellular signaling pathways by viral proteins.DNA integration to promote genome instability is a feature of HBV infection, and metabolic reprogramming leading to steatosis is driven by HCV infection. The current review aims to provide a brief overview of HBV, HCV and HDV molecular biology, and highlight specific viral-associated oncogenic mechanisms and common molecular pathways deregulated in HCC, and current as well as emerging treatments for HCC.  相似文献   

9.
Chronic hepatitis B(CHB) is a major global health problem affecting an estimated 350 million people with more than 786000 individuals dying annually due to complications, such as cirrhosis, liver failure and hepatocellular carcinoma(HCC). Liver transplantation(LT) is considered gold standard for treatment of hepatitis B virus(HBV)-related liver failure and HCC. However, post-transplant viral reactivation can be detrimental to allograft function, leading to poor survival. Prophylaxis with high-dose hepatitis B immunoglobulin(HBIG) and anti-viral drugs have achieved remarkable progress in LT by suppressingviral replication and improving long-term survival. The combination of lamivudine(LAM) plus HBIG has been for many years the most widely used. However, life-long HBIG use is both cumbersome and costly, whereas long-term use of LAM results in resistant virus. Recently, in an effort to develop HBIG-free protocols, high potency nucleos(t)ide analogues, such as Entecavir or Tenofovir, have been tried either as monotherapy or in combination with low-dose HBIG with excellent results. Current focus is on novel antiviral targets, especially for covalently closed circular DNA(ccc DNA), in an effort to eradicate HBV infection instead of viral suppression. However, there are several other molecular mechanisms through which HBV may reactivate and need equal attention. The purpose of this review is to address post-LT HBV reactivation, its risk factors, underlying molecular mechanisms, and recent advancements and future of anti-viral therapy.  相似文献   

10.
Hepatocellular carcinoma(HCC)is a complex disease that is dually challenging to treat due to underlying chronic liver disease in addition to the cancer itself.The prognosis of patients with HCC is determined by intrahepatic tumor status and reserved hepatic function.Hepatitis B virus(HBV)is an established major risk factor of HCC development,and HBV viral load is being increasingly recognized as a prognostic factor in the presence of established HCC.High HBV viral load may affect the prognosis of HBV-related HCC patients in several ways.First,it is associated with more frequent recurrence of HBV-related HCC after treatment.Second,it is associated with more occurrence and severity of potentially life-threatening HBV reactivation.Last,it is associated with more worsened liver function,which limits the therapeutic options for HBV-related HCC.HBV,directly or indirectly,can induce hepatocarcinogenesis.In patients with a high HBV DNA level and subsequent active hepatitis,adhesion molecules expressed on the sinusoidal cells are up-regulated and may increase intrahepatic metastasis.HCC progression after treatment can lead to a poor prognosis by reducing number of normal functioning hepatocytes.Thus,high HBV viral load can affect the prognosis of patientswith HCC by frequent recurrence after treatment for HCC and deterioration of hepatic function associated with HCC progression.Recent meta-analysis showed that antiviral treatment reduces HCC recurrence and liver-related mortality after curative therapy of HCC.Given the strong relationship between high HBV DNA load and poor survival outcome of HCC patients due to cancer progression,it is expected that long-term antiviral therapy results in the sustained HBV suppression,control of inflammation,reduction in HCC progression,and eventually in improved overall survival.  相似文献   

11.
Hepatocellular carcinoma(HCC)is a leading cause of cancer-related mortality worldwide,with the majority of cases associated with persistent infection from hepatitis B virus(HBV)or hepatitis C virus(HCV).Natural history studies have identified risk factors associated with HCC development among chronic HBV and HCV infection.High-risk infected individuals can now be identified by the usage of risk predictive scores.Vaccination plays a central role in the prevention of HBV-related HCC.Treatment of chronic HBV infection,especially by nucleoside analogue therapy,could also reduce the risk of HBV-related HCC.Concerning HCV infection,besides the advocation of universal precautions to reduce the rate of infection,pegylated interferon and ribavirin could also reduce the risk of HCV-related HCC among those achieving a sustained virologic response.Recently there has been mounting evidence on the role of chemopreventive agents in reducing HBV-and HCV-related HCC.The continued advances in the understanding of the molecular pathogenesis of HCC would hold promise in preventing this highly lethal cancer.  相似文献   

12.
Chronic hepatitis B is the main risk factor for hepatocellular carcinoma (HCC) in Asia. The most important preventive strategy's adoption of the universal hepatitis B vaccination program is now in its third decade. There is a clear reduction in both chronic hepatitis B virus (HBV) infection (hepatitis B surface antigen "carriage") but also in childhood HCC in Taiwan. An outstanding concern is variability in vaccine coverage between countries. For patients with chronic hepatitis B, serum HBV DNA levels have emerged as the key risk factor for development of HCC. The initial treatment for chronic hepatitis B was interferon. One randomized control trial, and several case–control or cohort studies have shown benefits for preventing HCC, particularly in cirrhotic patients who responded to therapy. With nucleos(t)ide analogs, the most important study has been the Asian Cirrhosis Lamivudine multicenter randomized controlled trial. This showed that lamivudine can reduce disease progression in HBV-related cirrhosis, including an approximately 50% decrease in HCC incidence. Such efficacy was achieved despite emergence of drug resistance in approximately 50% of cases. Case–control studies have suggested that hepatitis B cases without cirrhosis may also benefit. In conclusion, it is now possible to prevent HBV-related HCC. The most effective method is hepatitis B vaccination, which prevents chronic HBV infection and chronic liver disease resulting therefrom. Interferon therapy appears to confer benefit but the evidence is weaker. First-generation oral antiviral (lamivudine) reduces HCC risk, particularly in cirrhotics. Long-term outcome data with newer, more potent HBV antivirals that have a higher genetic barrier to drug resistance are eagerly awaited.  相似文献   

13.
Chronic hepatitis B (CHB) is associated with significant morbidity and mortality, due to the adverse sequelae of cirrhosis and hepatocellular carcinoma (HCC). To date, antiviral therapy has been reserved for patients with ostensibly active liver disease, fibrosis or cirrhosis, and/or increased risk of HCC. Historically, patients with hepatitis B ‘e’ antigen (HBeAg)-positive chronic infection, were not offered antiviral therapy. Nevertheless, there has been compelling evidence emerging in recent years, demonstrating that this disease phase is in fact not characterized by immunological tolerance. HBV integration into the human genome is a frequent event found in these patients. Additionally, it may well be associated with active inflammation and fibrosis, even in the presence of persistently normal liver enzymes. Likewise, it appears that the mechanisms of hepatocarcinogenesis are already present during this early stage of the disease. This was reflected in the European Association for the Study of the Liver (EASL) guidelines, where treating patients above the age of 30 years with HBeAg-positive chronic infection was proposed. Lowering the treatment threshold to broaden treatment eligibility is likely to slow disease progression and reduce the risk of developing HCC. The current review discusses the reasons to consider early antiviral therapy in HBeAg-positive chronic infection.  相似文献   

14.
15.
Hepatitis B viral genotypes: clinical relevance and molecular characteristics   总被引:19,自引:0,他引:19  
Hepatitis B virus (HBV) infection is a global health problem and the clinical outcome of chronic HBV infection depends on the frequency and severity of hepatitis flares in the immune clearance phase. Currently, four subtypes and seven genotypes of HBV are identified and most have specific geographic distributions. The impact of HBV genotypes on the clinical outcome of chronic HBV infection has been partially clarified. In Taiwan, genotype C is associated with more severe liver disease and genotype B is associated with the development of hepatocellular carcinoma (HCC) in young non-cirrhotic patients. In contrast, genotype B has a relatively good prognosis in Japan and China and is rarely associated with the development of HCC. Similarly, genotype D is associated with more severe liver disease than genotype A in India and may predict occurrence of HCC in young patients. Although superinfection of HBV on top of hepatitis B carriers occurs in Taiwan, it is rarely associated with acute exacerbations. As to the response to antiviral treatment, genotypes C and D are associated with a lower response rate to interferon therapy compared with genotypes B and A. In addition, the subtype adw is reported to be associated with a higher risk of lamivudine resistance than ayw. In HBV subtype adw-infected HCC patients, genotype B responds better to embolization therapy and has a lower rate of HCC recurrence than genotype C. In summary, pathogenic and therapeutic differences do exist among HBV genotypes and determining the genotype in patients with chronic HBV infection would help gain further information for etiologic, clinical, virologic and anthropologic investigations. Further studies to clarify the molecular virological factors that contribute to these differences are awaited.  相似文献   

16.
Chemoprevention of hepatocellular carcinoma (HCC) is listed as a yet highly debated long-term benefit of a successful treatment of patients with chronic viral hepatitis. In the hepatitis B virus (HBV) arena, the retrospective scrutiny of both interferon and nucleos(t)ide analogues (NUC) studies failed to provide robust evidence for HCC chemoprevention, due to a number of confoundings in the studies that were originally designed to assess the antiviral activity of interferon therapy. However, the reanalysis of outcomes following patients stratification for risk factors of HCC, provided a clue to find an association between NUC therapy and a reduced risk of liver cancer in non cirrhotic patients, only. In the hepatitis C scenario, a meta analysis of 30 observational studies of patients treated with interferon demonstrated a more than 70% reduction of HCC risk occurring independently of severity of underlying liver fibrosis which was less pronounced in aged patients and those with more advanced liver fibrosis. While the reasons for the residual risk of HCC in virological responders remain largely unexplained, international societies recommend surveillance for HCC of both HBV and HCV responders to antiviral therapy.  相似文献   

17.
BACKGROUND/AIMS: The long-term outcomes in hepatitis B e antigen (HBeAg)-negative chronic hepatitis B are distinct from those in HBeAg-positive chronic hepatitis. However, the molecular virological factors that contribute to the progression of liver disease in this special clinical setting remain largely unknown. We thus investigated the association of hepatitis B virus (HBV) genotypes as well as precore/basal core-promoter mutations with the clinical and virological characteristics of patients with HBeAg-negative chronic hepatitis B in Taiwan. METHODS: HBV genotypes and sequences of precore and basal core-promoter regions of the HBV genome were determined in 174 HBeAg-negative chronic HBV infection patients including 62 inactive carriers and 112 with different stages of liver disease. RESULTS: HBV carriers with older age (> 50 years) (odds ratio, 9.09; 95% confidence interval (CI), 3.22-25, P < 0.001) and basal core-promoter mutant of HBV (odds ratio, 4.12; 95% CI, 1.41-12.03, P = 0.01) were associated with the development of liver cirrhosis and hepatocellular carcinoma (HCC). The gender-related risk factors associated with the development of liver cirrhosis and HCC were further analyzed, and basal core-promoter mutant was only associated with the development of liver cirrhosis and HCC in male carriers (odds ratio, 4.35; 95% CI, 1.30-14.52, P = 0.02). CONCLUSIONS: The risk of development of liver cirrhosis and HCC is significantly increased in patients with advanced age as well as with basal core-promoter mutant of HBV. In addition, basal core-promoter mutant might contribute to the gender difference of the progression of liver disease in HBeAg-negative chronic hepatitis B in Taiwan.  相似文献   

18.
Epidemiological studies have provided overwhelming evidence for a causal role of chronic hepatitis B virus(HBV) infection in the development of hepatocellular carcinoma(HCC).However,the pathogenesis of HBV infection and carcinogenesis of HBV-associated HCC are still elusive.This review will summarize the current knowledge on the mechanisms involved in HBV-related liver carcinogenesis.The role of HBV in tumor formation appears to be complex,and may involve both direct and indirect mechanisms.Integration of H...  相似文献   

19.
Molecular characteristics and stages of chronic hepatitis B virus infection   总被引:1,自引:0,他引:1  
Hepatitis B virus (HBV) is a common viral pathogen that causes a substantial health burden worldwide. Remarkable progress has been made in our under- standing of the natural stages of chronic HBV infection. A dynamic balance between viral replication and host immune response is pivotal to the pathogenesis of liver disease. Knowledge of the HBV genome organization and replication cycle can unravel HBV genotypes and molecular variants, which contribute to the heterogeneity in outcome of chronic HBV infection. Most HBV infections are spontaneously resolved in immunocompetent adults, whereas they become chronic in most neonates and infants at a great risk of developing complications such as cirrhosis and hepatocellular carcinoma (HCC). Those with chronic HBV infection may present in one of the four phases of infection: immune tolerance, immune clearance [hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB)], inactive carrier state, and reactivation (HBeAg-negative CHB). Understanding the dynamic nature of chronic HBV infection is crucial in the management of HBV carriers. Long-term monitoring and optimal timing of antiviral therapy for chronic HBV infection help to prevent progression of HBV-related liver disease to its later stage, particularly in patients with higher risk markers of HCC, such as serum DNA concentration, HBeAg status, serum aminotransferase, HBV genotypes, and pre-core or core mutants.  相似文献   

20.
BACKGROUNDChina has a high prevalence of hepatitis B virus (HBV), but most chronic hepatitis B (CHB) patients do not receive standardized antiviral therapy. There are few relevant reports addressing the outcomes of the large number of CHB patients who do not receive antiviral therapy.AIMTo observe the outcomes of long-term follow-up of patients with CHB without antiviral treatment.METHODSThis study included 362 patients with CHB and 96 with hepatitis B cirrhosis without antiviral treatment and with only liver protection and anti-inflammatory treatment from 1993 to 1998. The median follow-up times were 10 and 7 years, respectively. A total of 203 CHB and 129 hepatitis B cirrhosis patients receiving antiviral therapy were selected as the control groups. The median follow-up times were 8 and 7 years, respectively. Kaplan-Meier curves were used to analyze the cumulative incidence of hepatocellular carcinoma (HCC), and the Cox regression model was used to analyze the risk factors for HCC.RESULTSAmong the patients in the non-antiviral group, 16.9% had spontaneous decreases in HBV DNA to undetectable levels, and 32.8% showed hepatitis B e antigen (HBeAg) seroconversion. In the antiviral group, 87.2% of patients had undetectable HBV DNA, and 52% showed HBeAg seroconversion. Among CHB and hepatitis B cirrhosis patients, the cumulative incidence rates of HCC were 14.9% and 53.1%, respectively, in the non-antiviral group and were 10.7% and 31.9%, respectively, in the antiviral group. There was no difference between the two groups regarding the CHB patients (P = 0.842), but there was a difference between the groups regarding the hepatitis B cirrhosis patients (P = 0.026). The cumulative incidence rates of HCC were 1.6% and 22.3% (P = 0.022) in the groups with and without spontaneous HBeAg seroconversion, respectively. The incidence rates of HCC among patients with and without spontaneous declines in HBV DNA to undetectable levels were 1.6% and 19.1%, respectively (P = 0.051). There was no difference in the cumulative incidence of HCC between the two groups regarding the patients with drug-resistant CHB (P = 0.119), but there was a significant difference between the two groups regarding the patients with cirrhosis (P = 0.004). The Cox regression model was used for regression of the corrected REACH-B score, which showed that alanine aminotransferase > 400 U/L, history of diabetes, and family history of liver cancer were risk factors for HCC among men aged > 40 years (P < 0.05). Multifactorial analysis showed that a family history of HCC among men was a risk factor for HCC.CONCLUSIONAntiviral therapy and non-antiviral therapy with liver protection and anti-inflammatory therapy can reduce the risk of HCC. Antiviral therapy may mask the spontaneous serological response of some patients during CHB. Therefore, the effect of early antiviral therapy on reducing the incidence of HCC cannot be overestimated.  相似文献   

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