scholarly journals In Vitro Activity and Mechanism of Action of Methylenecyclopropane Analogs of Nucleosides against Herpesvirus Replication

2005 ◽  
Vol 49 (3) ◽  
pp. 1039-1045 ◽  
Author(s):  
Earl R. Kern ◽  
Nicole L. Kushner ◽  
Caroll B. Hartline ◽  
Stephanie L. Williams-Aziz ◽  
Emma A. Harden ◽  
...  
Keyword(s):  
Mechanism Of Action ◽  
Human Herpesvirus ◽  
Murine Cytomegalovirus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Herpesvirus Type ◽  
Varicella Zoster ◽  
Barr Virus ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT We have reported previously that methylenecyclopropane analogs of nucleosides have excellent activity against certain members of the herpesvirus family. A second generation, the 2,2-bis-hydroxymethyl derivatives, were synthesized, and 18 compounds were tested for activity in vitro against herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), human and murine cytomegalovirus (HCMV and MCMV), varicella-zoster virus (VZV), and Epstein-Barr virus (EBV). Selected analogs were also evaluated against human herpesvirus type 6 (HHV-6) and HHV-8. None of the 18 compounds had activity against HSV-1 or HSV-2, but four were active against VZV by plaque reduction (PR) assay at 50% effective concentration (EC50) levels of ≤50 μM. Six of the 18 compounds were active against HCMV by cytopathic effect or PR assays with EC50s of 0.5 to 44 μM, and all were active against MCMV by PR (0.3 to 54 μM). Four of the compounds were active against EBV by enzyme-linked immunosorbent assay (<0.3 to 4.4 μM). Four compounds with CMV activity were also active against HHV-6A and HHV-6B (0.7 to 28 μM), and three compounds were active against HHV-8 (5.5 to 16 μM). One of these, ZSM-I-62, had particularly good activity against CMV, HHV-6, and HHV-8, with EC50s of 0.7 to 8 μM. Toxicity was evaluated in adherent and nonadherent cells, and minimal cytotoxicity was observed. Mechanism of action studies with HCMV suggested that these compounds are phosphorylated by the ppUL97 phosphotransferase and are potent inhibitors of viral DNA synthesis. These results indicate that at least one of these compounds may have potential for use in treating CMV and other herpesvirus infections in humans.

scholarly journals Inhibition of Herpesvirus Replication by 5-Substituted 4′-Thiopyrimidine Nucleosides

2009 ◽  
Vol 53 (12) ◽  
pp. 5251-5258 ◽  
Author(s):  
Mark N. Prichard ◽  
Debra C. Quenelle ◽  
Caroll B. Hartline ◽  
Emma A. Harden ◽  
Geraldine Jefferson ◽  
...  
Keyword(s):  
Human Herpesvirus ◽  
Good Activity ◽  
Varicella Zoster ◽  
Barr Virus ◽  
Resistant Strains ◽  
Epstein Barr ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT A series of 4′-thionucleosides were synthesized and evaluated for activities against orthopoxviruses and herpesviruses. We reported previously that one analog, 5-iodo-4′-thio-2′-deoxyuridine (4′-thioIDU), exhibits good activity both in vitro and in vivo against two orthopoxviruses. This compound also has good activity in cell culture against many of the herpesviruses. It inhibited the replication of herpes simplex virus type 1 (HSV-1), HSV-2, and varicella-zoster virus with 50% effective concentrations (EC50s) of 0.1, 0.5, and 2 μM, respectively. It also inhibited the replication of human cytomegalovirus (HCMV) with an EC50 of 5.9 μM but did not selectively inhibit Epstein-Barr virus, human herpesvirus 6, or human herpesvirus 8. While acyclovir-resistant strains of HSV-1 and HSV-2 were comparatively resistant to 4′-thioIDU, it retained modest activity (EC50s of 4 to 12 μM) against these strains. Some ganciclovir-resistant strains of HCMV also exhibited reduced susceptibilities to the compound, which appeared to be related to the specific mutations in the DNA polymerase, consistent with the observed incorporation of the compound into viral DNA. The activity of 4′-thioIDU was also evaluated using mice infected intranasally with the MS strain of HSV-2. Although there was no decrease in final mortality rates, the mean length of survival after inoculation increased significantly (P < 0.05) for all animals receiving 4′-thioIDU. The findings from the studies presented here suggest that 4′-thioIDU is a good inhibitor of some herpesviruses, as well as orthopoxviruses, and this class of compounds warrants further study as a therapy for infections with these viruses.

scholarly journals Comparative Activities of Lipid Esters of Cidofovir and Cyclic Cidofovir against Replication of Herpesviruses In Vitro

2005 ◽  
Vol 49 (9) ◽  
pp. 3724-3733 ◽  
Author(s):  
Stephanie L. Williams-Aziz ◽  
Caroll B. Hartline ◽  
Emma A. Harden ◽  
Shannon L. Daily ◽  
Mark N. Prichard ◽  
...  
Keyword(s):  
Human Cytomegalovirus ◽  
Human Herpesvirus ◽  
Murine Cytomegalovirus ◽  
In Vitro Assays ◽  
Varicella Zoster ◽  
Barr Virus ◽  
Lipid Ester ◽  
Epstein Barr ◽  
Simplex Virus

ABSTRACT Cidofovir (CDV) is an effective therapy for certain human cytomegalovirus (HCMV) infections in immunocompromised patients that are resistant to other antiviral drugs, but the compound is not active orally. To improve oral bioavailability, a series of lipid analogs of CDV and cyclic CDV (cCDV), including hexadecyloxypropyl-CDV and -cCDV and octadecyloxyethyl-CDV and -cCDV, were synthesized and found to have multiple-log-unit enhanced activity against HCMV in vitro. On the basis of the activity observed with these analogs, additional lipid esters were synthesized and evaluated for their activity against herpes simplex virus (HSV) types 1 and 2, human cytomegalovirus, murine cytomegalovirus, varicella-zoster virus (VZV), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV-6), and HHV-8. Using several different in vitro assays, concentrations of drug as low as 0.001 μM reduced herpesvirus replication by 50% (EC50) with the CDV analogs, whereas the cCDV compounds were generally less active. In most of the assays performed, the EC50 values of the lipid esters were at least 100-fold lower than the EC50 values for unmodified CDV or cCDV. The lipid analogs were also active against isolates that were resistant to CDV, ganciclovir, or foscarnet. These results indicate that the lipid ester analogs are considerably more active than CDV itself against HSV, VZV, CMV, EBV, HHV-6, and HHV-8 in vitro, suggesting that they may have potential for the treatment of infections caused by a variety of herpesviruses.

scholarly journals In Vitro Activities of Benzimidazole d- and l-Ribonucleosides against Herpesviruses

2003 ◽  
Vol 47 (7) ◽  
pp. 2186-2192 ◽  
Author(s):  
Stephanie L. Williams ◽  
Caroll B. Hartline ◽  
Nicole L. Kushner ◽  
Emma A. Harden ◽  
Deborah J. Bidanset ◽  
...  
Keyword(s):  
Clinical Manifestations ◽  
Human Herpesvirus ◽  
Significant Activity ◽  
Varicella Zoster ◽  
Barr Virus ◽  
Culture Cells ◽  
Simplex Virus ◽  
Human Cmv ◽  
Hsv 1

ABSTRACT Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), varicella-zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV-6), and human herpesvirus 8 (HHV-8) are responsible for a number of clinical manifestations in both normal and immunocompromised individuals. The parent benzimidazole ribonucleosides evaluated in this series, 2-bromo-5,6-dichloro-1-(β-d-ribofuranosyl)benzimidazole (BDCRB) and maribavir (1263W94), are potent and selective inhibitors of human CMV replication. These nucleosides act by two different mechanisms. BDCRB blocks the processing and maturation of viral DNA, whereas 1263W94 inhibits the viral enzyme pUL97 and interferes with DNA synthesis. In the present study, we have evaluated the in vitro antiviral activity of BDCRB, an analog, GW275175X (175X), and 1263W94 against the replication of HSV-1, HSV-2, VZV, CMV, EBV, HHV-6, and HHV-8. By using various methodologies, significant activity was observed against human CMV and EBV but not against HSV-1, HSV-2, VZV, HHV-6, or HHV-8. Plaque reduction assays performed on a variety of laboratory and clinical isolates of human CMV indicated that all strains, including those resistant to ganciclovir (GCV) and foscarnet, were sensitive to all three benzimidazole ribonucleosides, with mean 50% effective concentration values of about 1 to 5 μM compared to that of GCV at 6 μM. The toxicity of these compounds in tissue culture cells appeared to be similar to that observed with GCV. These results demonstrate that the benzimidazole ribonucleosides are active against human CMV and EBV and suggest that they may be useful for the treatment of infections caused by these herpesviruses.

scholarly journals Amphipathic DNA Polymers Exhibit Antiherpetic Activity In Vitro and In Vivo

2008 ◽  
Vol 52 (8) ◽  
pp. 2727-2733 ◽  
Author(s):  
David I. Bernstein ◽  
Nathalie Goyette ◽  
Rhonda Cardin ◽  
Earl R. Kern ◽  
Guy Boivin ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Broad Spectrum ◽  
Parent Compound ◽  
Human Herpesvirus ◽  
Varicella Zoster ◽  
Barr Virus ◽  
Simplex Virus ◽  
Acid Stable

ABSTRACT Phosphorothioated oligonucleotides have a sequence-independent antiviral activity as amphipathic polymers (APs). The activity of these agents against herpesvirus infections in vitro and in vivo was investigated. The previously established sequence-independent, phosphorothioation-dependent antiviral activity of APs was confirmed in vitro by showing that a variety of equivalently sized homo- and heteropolymeric AP sequences were similarly active against herpes simplex virus type 1 (HSV-1) infection in vitro compared to the 40mer degenerate parent compound (REP 9), while the absence of phosphorothioation resulted in the loss of antiviral activity. In addition, REP 9 demonstrated in vitro activity against a broad spectrum of other herpesviruses: HSV-2 (50% effective concentration [EC50], 0.02 to 0.06 μM), human cytomegalovirus (EC50, 0.02 to 0.13 μM), varicella zoster virus (EC50, <0.02 μM), Epstein-Barr virus (EC50, 14.7 μM) and human herpesvirus types 6A/B (EC50, 2.9 to 10.2 μM). The murine microbicide model of genital HSV-2 was then used to evaluate in vivo activity. REP 9 (275 mg/ml) protected 75% of animals from disease and infection when provided 5 or 30 min prior to vaginal challenge. When an acid-stable analog (REP 9C) was used, 75% of mice were protected when treated with 240 mg/ml 5 min prior to infection (P < 0.001), while a lower dose (100 mg/ml) protected 100% of the mice (P < 0.001). The acid stable REP 9C formulation also provided protection at 30 min (83%, P < 0.001) and 60 min (50%, P = 0.07) against disease. These observations suggest that APs may have microbicidal activity and potential as broad-spectrum antiherpetic agents and represent a novel class of agents that should be studied further.

scholarly journals Antiherpesvirus Activities of Two Novel 4′-Thiothymidine Derivatives, KAY-2-41 and KAH-39-149, Are Dependent on Viral and Cellular Thymidine Kinases

2014 ◽  
Vol 58 (8) ◽  
pp. 4328-4340 ◽  
Author(s):  
Natacha Coen ◽  
Sophie Duraffour ◽  
Kazuhiro Haraguchi ◽  
Jan Balzarini ◽  
Joost J. van den Oord ◽  
...  
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Antiviral Activity ◽  
Epstein Barr Virus ◽  
Varicella Zoster ◽  
Barr Virus ◽  
Epstein Barr ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACTThe emergence of drug-resistant herpesviruses represents a significant problem in clinical practice, primarily in immunocompromised patients. Furthermore, effective antiviral therapies against gammaherpesvirus-associated diseases are lacking. Here, we present two thiothymidine derivatives, KAY-2-41 and KAH-39-149, with different spectra of antiviral activity from those of the reference antiherpetic drugs, showing inhibitory activities against herpes simplex virus, varicella-zoster virus (VZV), and particularly against Epstein-Barr virus, with high selectivityin vitro. While KAY-2-41- and KAH-39-149-resistant herpesviruses were found to harbor mutations in the viral thymidine kinase (TK), these mutations conferred only low levels of resistance to these drugs but high levels to other TK-dependent drugs. Also, antiviral assays in HeLa TK-deficient cells showed a lack of KAY-2-41 and KAH-39-149 activities against herpes simplex virus 1 (HSV-1) and HSV-2 TK-deficient mutants. Furthermore, enzymatic TK assays showed the ability of HSV-1 TK, VZV TK, and cellular TK1 and TK2 to recognize and phosphorylate KAY-2-41 and KAH-39-149. These results demonstrate that the compounds depend on both viral and host TKs to exert antiviral activity. Additionally, the antiviral efficacy of KAH-39-149 proved to be superior to that of KAY-2-41 in a mouse model of gammaherpesvirus infection, highlighting the potential of this class of antiviral agents for further development as selective therapeutics against Epstein-Barr virus.

scholarly journals (Z)- and (E)-2-(Hydroxymethylcyclopropylidene)-Methylpurines and Pyrimidines as Antiviral Agents

1998 ◽  
Vol 9 (4) ◽  
pp. 57-68 ◽  
Author(s):  
Y-L Qiu ◽  
RG Ptak ◽  
JM Breitenbach ◽  
J-S Lin ◽  
Y-C Cheng ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Antiviral Agents ◽  
Human Herpesvirus ◽  
Murine Cytomegalovirus ◽  
Strong Inhibitor ◽  
Varicella Zoster ◽  
Daudi Cells ◽  
Hiv 1 ◽  
Hsv 1

Several Z- and E-methylenecyclopropane nucleoside analogues were synthesized and evaluated for antiviral activity. Reaction of the Z- and E-2-amino-6-chloropurine methylenecyclopropanes with ammonia or cyclopropylamine gave 2,6-diamino or 2-amino-6-cyclopropylamino analogues. Alkylation elimination of N4-acetylcytosine with ethyl Z- and E-2-bromo-2-bromomethylcyclopropane-1-carboxylates gave a mixture of the Z-and E-methylenecyclopropane derivatives of cytosine. Reduction furnished a mixture of syncytol and the E isomer. Benzoylation led to the respective N4-benzoyl derivatives which were separated by chromatography. Debenzoylation afforded pure syncytol and the E isomer. Alkylation of 2,4-bis-O-trimethylsilylthymine with ethyl Z- and E-2-bromo-2-bromomethylcyclopropane-1-carboxylates gave the corresponding Z- and E-1-bromo-cyclopropylmethylderivatives of thymine. Base-catalysed elimination of HBr gave Z- and E-methylenecyclopropane carboxylic esters. Reduction furnished, after chromatographic separation, synthymol and the E isomer. The Z/E isomeric assignment of the obtained products followed from 1H NMR spectroscopy. The methylenecyclopropane analogues were tested for antiviral activity in vitro against human and murine cytomegalovirus (HCMV, MCMV), Epstein–Barr virus (EBV), varicella zoster virus (VZV), hepatitis B virus (HBV), herpes simplex virus types 1 and 2 (HSV-1, HSV-2), human herpesvirus 6 (HHV-6) and human immunodeficiency virus type 1 (HIV-1). The Z-2-amino-6-cyclopropylaminopurine analogue was the most effective agent against HCMV (EC50 or EC90 0.4–2 μM) followed by syncytol and the Z-2,6-diaminopurine analogues (EC50 or EC90 3.4–29 and 11–24 μM, respectively). The latter compound was also a strong inhibitor of MCMV (EC50 0.6 μM). Syncytol was the most potent against EBV (EC50 <0.41 and 2.5 μM) followed by the Z-2,6-diaminopurine (EC50 1.5 and 6.9 μM) and the Z-2-amino-6-cyclopropylaminopurine derivative (EC50 11.8 μM). Syncytol was also most effective against VZV (EC50 3.6 μM). Activity against HSV-1, HSV-2 and HHV-6 was generally lower; synthymol had an EC50 of 2 μM against HSV-1 (ELISA) and 1.3 μM against EBV in Daudi cells but was inactive in other assays. The 2-amino-6-cyclopropylamino analogue displayed EC50 values between 215 and >74 μM in HSV-1 and HSV-2 assays. 2-Amino-6-cyclopropylaminopurine and 2,6-diaminopurine derivatives were effective against HBV (EC50 2 and 10 μM, respectively), whereas none of the analogues inhibited HIV-1 at a higher virus load. Syncytol and the E isomer were equipotent against EBV in Daudi cells but the E isomer was much less effective in DNA hybridization assays. The E-2,6-diaminopurine analogue and E isomer of synthymol were devoid of antiviral activity.

Herpesviridae Seropositivity in Patients with Multiple Sclerosis: First Polish Study

2018 ◽  
Vol 80 (5-6) ◽  
pp. 229-235 ◽  
Author(s):  
Agata Czarnowska ◽  
Katarzyna Kapica-Topczewska ◽  
Olga Zajkowska ◽  
Renata Świerzbińska ◽  
Monika Chorąży ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Human Herpesvirus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Control Group ◽  
Varicella Zoster ◽  
Barr Virus ◽  
North Eastern ◽  
Epstein Barr ◽  
Simplex Virus ◽  
The Impact

Background: Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system that leads to inflammation, demyelination and neurodegeneration. Viral aetiology has been suspected to be an MS trigger for a long time, and herpesviruses (HSs) are among the potential pathogens involved. Objectives: The present investigation aims to detect the presence of antibodies against the herpes simplex virus (HSV), varicella-zoster virus, Epstein-Barr virus (EBV), human cytomegalovirus (CMV) and human herpesvirus 6 (HHV6) in the serum of MS patients and control individuals in north-eastern Poland. Method: Plasma was collected from 141 MS patients and 44 blood donors who served as the control group. These individuals were assessed for the presence of antibodies using an enzyme-linked immunosorbent assay. Results: The statistical analysis showed a higher probability of EBV (p = 0.037, OR 4.359) and HHV6 (p = 0.020, OR 3.343) antibody presence in patients with MS compared to that in the control group. In the MS patient group, the prevalence of CMV IgG antibodies was significantly higher in females (p = 0.025). Patients who tested positive for anti-EBV IgG were diagnosed 7.9 years earlier than patients who tested negative for anti-EBV IgG (p = 0.048). Conclusions: The study showed that MS patients in north-eastern Poland were more likely to be seropositive for EBV and HHV6 than healthy individuals. Further work should be undertaken in other regions of Poland and other European countries with particular attention paid to testing seropositivity in all HSs, particularly in the MS patient population, to evaluate the impact of HSs on MS patients in different environments.

scholarly journals Amplification of the Six Major Human Herpesviruses from Cerebrospinal Fluid by a Single PCR

1999 ◽  
Vol 37 (4) ◽  
pp. 950-953 ◽  
Author(s):  
Sophie Minjolle ◽  
C. Michelet ◽  
I. Jusselin ◽  
M. Joannes ◽  
F. Cartier ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Clinical Signs ◽  
Human Herpesvirus ◽  
Varicella Zoster ◽  
Consensus Sequences ◽  
Barr Virus ◽  
Two Samples ◽  
Epstein Barr ◽  
Simplex Virus ◽  
Hsv 1

We used a novel type of primer system, a system that uses stair primers, in which the primer sequences are based on consensus sequences in the DNA polymerase gene of herpesvirus to detect herpesviruses by PCR. A single PCR in a single tube detected the six major herpesviruses that infect the central nervous system: herpes simplex virus type 1 (HSV-1), and type 2 (HSV-2), cytomegalovirus (CMV), Epstein-Barr virus (EBV), varicella-zoster virus (VZV), and human herpesvirus 6 (HHV-6). We used the technique to analyze 142 cerebrospinal fluid (CSF) samples that had been stored at −80°C and compared the results with those obtained previously for the same samples by standard, targeted PCR. Four hundred one targeted PCR tests had been run with the 142 samples to detect HSV-1, HSV-2, CMV, and VZV; screening for EBV and HHV-6 was not prescribed when the samples were initially taken. Eighteen CSF samples tested positive by classic targeted PCR. The herpesvirus consensus PCR detected herpesviruses in 37 samples, including 3 samples with coinfections and 17 viral isolates which were not targeted. Two samples identified as infected by the targeted PCR tested negative by the consensus PCR, and eight samples that tested positive by the consensus PCR were negative by the targeted PCR. One hundred three samples scored negative by both the targeted and the consensus PCRs. This preliminary study demonstrates the value of testing for six different herpesviruses simultaneously by a sensitive and straightforward technique rather than screening only for those viruses that are causing infections as suggested by clinical signs.

scholarly journals Encephalitis in Thailand: A Neglected Disease Increasingly Caused by Enterovirus

2021 ◽  
Vol 6 (3) ◽  
pp. 117
Author(s):  
Pasin Hemachudha ◽  
Sininat Petcharat ◽  
Soawapak Hinjoy ◽  
Abhinbhen W. Saraya ◽  
Thiravat Hemachudha
Keyword(s):  
Human Herpesvirus ◽  
Health Science ◽  
Science Center ◽  
Varicella Zoster ◽  
Barr Virus ◽  
Specific Pcr ◽  
Epstein Barr ◽  
Simplex Virus ◽  
Made In ◽  
Hsv 1

From 2013 to 2018, the Thai Red Cross Emerging Infectious Disease–Health Science Center (TRC-EID-HS), in collaboration with the Department of Disease Control (DDC) and the Ministry of Public Health (MOPH) Thailand, conducted encephalitis surveillance. A total of 1700 cerebrospinal fluid (CSF) samples from patients with encephalitis were tested by a predesigned multiplex PCR. Diagnosis was made in 318 cases (18.7%), 86 (27%) of which were caused by Epstein–Barr virus (EBV), 55 (17.3%) by enteroviruses (EV), 36 (11.3%) by varicella–zoster virus (VZV), 31 (9.7%) by cytomegalovirus (CMV), 25 (7.8%) by herpes simplex virus type 1 (HSV-1), and 20 (6.3%) by human herpesvirus 6 (HHV-6). Results were compared with 3099 CSF samples from patients with encephalitis collected between 2002 to 2012, which were tested by specific PCR assays. Diagnosis was made in 337 (10.9%) of these cases, and 91 (27%) were CMV, 79 (23.4%) were VZV, 72 (21.4%) were EBV, 39 (11.6%) were EVs, 39 (11.6%) were HSV-1, 33 (9.8%) were HSV-2, and 2 (0.6%) were Dengue virus (DENV). The change in the pattern toward EVs as a major cause of viral encephalitis was unexpected, and a change in viral neurotropism may be responsible.

scholarly journals A Deubiquitinating Activity Is Conserved in the Large Tegument Protein of the Herpesviridae

2005 ◽  
Vol 79 (24) ◽  
pp. 15582-15585 ◽  
Author(s):  
Christian Schlieker ◽  
Gregory A. Korbel ◽  
Lisa M. Kattenhorn ◽  
Hidde L. Ploegh
Keyword(s):  
Epstein Barr Virus ◽  
Murine Cytomegalovirus ◽  
Tegument Protein ◽  
Herpes Simplex Virus 1 ◽  
Barr Virus ◽  
Essential Function ◽  
Epstein Barr ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT The largest tegument protein of herpes simplex virus 1 (HSV-1), UL36, contains a novel deubiquitinating activity embedded in it. All members of the Herpesviridae contain a homologue of HSV-1 UL36, the N-terminal segments of which show perfect conservation of those residues implicated in catalysis. For murine cytomegalovirus and Epstein-Barr virus, chosen as representatives of the beta- and gammaherpesvirus subfamilies, respectively, we here show that the homologous modules indeed display deubiquitinating activity in vitro. The conservation of this activity throughout all subfamilies is indicative of an important, if not essential, function.

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