RESUMEN
Prion diseases are fatal and malignant infectious encephalopathies induced by the pathogenic form of prion protein (PrPSc) originating from benign prion protein (PrPC). A previous study reported that the M132L single nucleotide polymorphism (SNP) of the prion protein gene (PRNP) is associated with susceptibility to chronic wasting disease (CWD) in elk. However, a recent meta-analysis integrated previous studies that did not find an association between the M132L SNP and susceptibility to CWD. Thus, there is controversy about the effect of M132L SNP on susceptibility to CWD. In the present study, we investigated novel risk factors for CWD in elk. We investigated genetic polymorphisms of the PRNP gene by amplicon sequencing and compared genotype, allele, and haplotype frequencies between CWD-positive and CWD-negative elk. In addition, we performed a linkage disequilibrium (LD) analysis by the Haploview version 4.2 program. Furthermore, we evaluated the 3D structure and electrostatic potential of elk prion protein (PrP) according to the S100G SNP using AlphaFold and the Swiss-PdbViewer 4.1 program. Finally, we analyzed the free energy change of elk PrP according to the S100G SNP using I-mutant 3.0 and CUPSAT. We identified 23 novel SNP of the elk PRNP gene in 248 elk. We found a strong association between PRNP SNP and susceptibility to CWD in elk. Among those SNP, S100G is the only non-synonymous SNP. We identified that S100G is predicted to change the electrostatic potential and free energy of elk PrP. To the best of our knowledge, this was the first report of a novel risk factor, the S100G SNP, for CWD.
Asunto(s)
Ciervos , Priones , Enfermedad Debilitante Crónica , Animales , Proteínas Priónicas/genética , Proteínas Priónicas/metabolismo , Priones/genética , Enfermedad Debilitante Crónica/genética , Enfermedad Debilitante Crónica/patología , Polimorfismo de Nucleótido Simple , Ciervos/genética , Factores de RiesgoRESUMEN
Chronic wasting disease (CWD) is caused by abnormal deleterious prion protein (PrPSc), and transmissible spongiform encephalopathy occurs in the Cervidae family. In recent studies, the susceptibility of prion disease has been affected by polymorphisms of the prion gene family. However, the study of the prion-related protein gene (PRNT) is rare, and the DNA sequence of this gene was not fully reported in all Cervidae families. In the present study, we amplified and first identified PRNT DNA sequences in the Cervidae family, including red deer, elk, sika deer and Korean water deer, using polymerase chain reaction (PCR). We aligned nucleotide sequences of the PRNT gene and the amino acid sequences of prion-related protein (Prt) protein among several species. In addition, we performed phylogenetic analysis to measure the evolutionary relationships of the PRNT gene in the Cervidae family. Furthermore, we performed homology modeling of the Prt protein using SWISS-MODEL and compared the structure of Prt protein between sheep and the Cervidae family using the Swiss-PdbViewer program. We obtained much longer PRNT sequences of red deer compared to the PRNT gene sequence registered in GenBank. Korean water deer denoted more close evolutionary distances with goats and cattle than the Cervidae family. We found 6 Cervidae family-specific amino acids by the alignment of Prt amino acid sequences. There are significantly different distributions of hydrogen bonds and the atomic distance of the N-terminal tail and C-terminal tail between sheep and the Cervidae family. We also detected the mRNA expression of PRNT gene in 3 tissues investigated. To our knowledge, this report is the first genetic study of the PRNT gene in the Cervidae family.
Asunto(s)
Ciervos/genética , Priones/genética , Enfermedad Debilitante Crónica/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Expresión Génica , Modelos Moleculares , Priones/química , Conformación Proteica , ARN Mensajero/genéticaRESUMEN
African swine fever (ASF) is a fatal contagious disease affecting swine. The first Korean ASF virus (ASFV) isolate (Korea/Pig/Paju1/2019) was used to compare the disease course of ASFV in pigs inoculated via the four routes. In the challenge experiment, domestic pigs were infected via the intraoral (IO) and intranasal (IN) routes with a 106 50% hemadsorbing dose (HAD50) and an intramuscular (IM) injection of 103 HAD50. In the direct contact (DC) group, five naïve pigs were brought into direct contact with two IM-ASFV-infected pigs. IO-, IN-, and IM-inoculated pigs showed similar disease courses, whereas DC pigs had comparable ASF syndrome after a 7-day latent period. The disease course in the DC route, one of the most common routes of infection, was not significantly different from that in the IO and IN routes. IM and DC groups differed in terms of the severity of fever and hemorrhagic lesions in the lymph nodes and spleen, indicating that the IM route, suitable for early vaccine development trials, is not appropriate for studying the ASFV infection mechanism, including early stage of infection, and IO and IN challenges with a designated dose can be alternatives in trials for assessing ASFV pathogenicity and vaccine efficacy investigations.
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Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Porcinos , Animales , Sus scrofa , Virulencia , República de CoreaRESUMEN
An outbreak of foot-and-mouth disease caused by serotype O virus occurred in cattle and pigs in South Korea during November 2010-April 2011. The highest rates of case and virus detection were observed 44 days after the first case was detected. Detection rates declined rapidly after culling and completion of a national vaccination program.
Asunto(s)
Enfermedades de los Bovinos/epidemiología , Brotes de Enfermedades , Virus de la Fiebre Aftosa/genética , Fiebre Aftosa/epidemiología , Enfermedades de los Porcinos/epidemiología , Proteínas Virales/genética , Animales , Bovinos , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/virología , Fiebre Aftosa/prevención & control , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/clasificación , Virus de la Fiebre Aftosa/aislamiento & purificación , Humanos , Filogenia , Prevalencia , República de Corea/epidemiología , Serotipificación , Porcinos , Enfermedades de los Porcinos/prevención & control , Enfermedades de los Porcinos/virología , Vacunación , Proteínas Virales/clasificación , Proteínas Virales/aislamiento & purificación , Vacunas Virales/administración & dosificaciónRESUMEN
Synucleinopathies are characterized by the deposition of alpha-synuclein (α-syn) aggregates in brain tissue. Pathological α-syn aggregates propagate in a prion-like manner and display prion-like biochemical properties. Using RT-QuIC, we measured α-syn seeding activity from brains of Dementia with Lewy body (DLB) patients post autoclave. Here, we show that autoclaving at 121 °C removes one to two log10 of α-syn seeding activity but the remaining 50% seeding dose (SD50) is more than 107/mg tissue. DLB brain samples autoclaved at 132 °C still revealed an SD50 of approximately 106/mg tissue. Our data suggest that DLB α-syn seeds are incompletely inactivated by standard autoclave, thus highlighting the need for evaluating laboratory procedures that fully inactivate them.
RESUMEN
Prion diseases are transmissible spongiform encephalopathies caused by deleterious prion protein (PrPSc ) derived from normal prion protein (PrPC ), which is encoded by the prion protein gene (PRNP). We performed an in-depth examination to detect PrPSc by using enzyme immunoassay (EIA), real-time quaking-induced conversion reactions (RT-QuIC) and protein misfolding cyclic amplification (PMCA) in nine brain tissues derived from three Holstein cattle carrying the E211K somatic mutation of the bovine PRNP gene. The EIA, RT-QuIC and PMCA analyses were not able to detect the PrPSc band in any tested samples. To the best of our knowledge, this report is the first to describe an in-depth examination of PrPSc in cattle carrying the E211K somatic mutation of the bovine PRNP gene.
Asunto(s)
Enfermedades de los Bovinos , Encefalopatía Espongiforme Bovina , Enfermedades por Prión , Priones , Animales , Bovinos , Encefalopatía Espongiforme Bovina/diagnóstico , Encefalopatía Espongiforme Bovina/genética , Mutación , Enfermedades por Prión/genética , Enfermedades por Prión/veterinaria , Proteínas Priónicas/genética , Proteínas Priónicas/metabolismoRESUMEN
BACKGROUND: Chronic wasting disease (CWD) is a cervid prion disease that is caused by abnormal prion protein (PrPSc ). Recent studies have reported that prion family genes showed a strong association with the susceptibility of several types of prion diseases. To date, an association study of the prion-related protein gene (PRNT) has not been performed in any type of cervid prion disease. METHODS: In the present study, we investigated PRNT polymorphisms in large deer, including 235 elk, 257 red deer and 150 sika deer. We compared genotype, allele and haplotype frequencies of PRNT polymorphisms between CWD-negative animals and CWD-positive animals to find an association of PRNT polymorphisms with the susceptibility of CWD. RESULTS: We found a total of five novel single nucleotide polymorphisms (SNPs) in the cervid PRNT gene. Interestingly, we observed significantly different distributions of genotypes and allele frequencies of three PRNT SNPs, including c.108C>T, c.159+30C>T and c.159+32A>C, between CWD-negative and CWD-positive red deer. In addition, significant differences of two haplotype frequencies in red deer were found between the CWD-negative and CWD-positive groups. However, the association identified in the red deer was not found in elk and sika deer. CONCLUSION: To the best of our knowledge, this report is the first to describe the strong association of PRNT SNPs with the susceptibility of CWD.
Asunto(s)
Ciervos , Priones , Enfermedad Debilitante Crónica , Animales , Ciervos/clasificación , Ciervos/genética , Genotipo , Polimorfismo de Nucleótido Simple , Priones/genética , Enfermedad Debilitante Crónica/genéticaRESUMEN
African swine fever (ASF) was first reported in South Korea in September 2019, and as of 31 December 2021, a total of 21 cases in domestic pig farms and 1875 ASFV-infected wild boars have been confirmed in the country. With the continued circulation of ASF in wild boars, and subsequent outbreaks in domestic pigs, concerns were raised about the possible changes in virulence occurring among African swine fever viruses (ASFV) circulating in South Korea. In this study, four Korean ASFV strains isolated from domestic pig farms at different time points between 2019 and 2021 were chosen, and used to experimentally infect domestic pigs by intramuscular inoculation to compare their virulence. All challenged pigs died at 4-9 days post-inoculation, with many showing clinical symptoms of fever, depression, loss of appetite, and recumbency. Gross lesions observed at necropsy included enlargement and hemorrhage of the lymph nodes and hydropericardium. The study showed that all four Korean ASFV isolates caused acute forms of illness, which supports the view that virulence among the circulating ASFV isolates in South Korea remained unchanged and highly virulent during this period.
Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Porcinos , Animales , Humanos , Fiebre Porcina Africana/epidemiología , Granjas , Virulencia , Sus scrofa , República de Corea/epidemiologíaRESUMEN
Prion diseases are incurable neurodegenerative disorders caused by proteinase K-resistant prion protein (PrPSc ) derived from normal prion protein (PrPC ) encoded by the prion protein gene (PRNP). Although the cervid PRNP gene plays a pivotal role in the pathological mechanism of chronic wasting disease (CWD), there is no existing association analysis between susceptibility to CWD and genetic polymorphisms of the PRNP gene in sika deer. We investigated genetic polymorphisms of the PRNP gene using amplicon sequencing in sika deer. In addition, to identify a genetic susceptibility factor, we compared the genotype, allele and haplotype frequencies of the PRNP gene between CWD-positive and CWD-negative sika deer. Furthermore, to assess the effect of the genetic polymorphisms on sika deer prion protein (PrP), we performed in silico analysis using PolyPhen-2, PROVEAN and AMYCO. Finally, we analysed the tertiary structure and electrostatic potential of sika deer PrP based on single nucleotide polymorphisms (SNPs) using the SWISS-MODEL and Swiss-PdbViewer programs. We found a total of 24 SNPs of the PRNP gene, including 22 novel SNPs (10 synonymous SNPs and 12 nonsynonymous SNPs), in sika deer. Among the nonsynonymous SNPs, we found a strong association of susceptibility to CWD with c.56G > A (Ser19Asn). In addition, we found that c.56G > A (Ser19Asn), c.296A > T (His99Leu) and c.560T > A (Val187Asp) were predicted to have damaging effects on sika deer PrP. Furthermore, we observed significant alterations in the electrostatic potential of sika deer PrP by genetic polymorphisms of the 187Asp allele. To the best of our knowledge, this was the first association study between genetic polymorphisms of the PRNP gene and susceptibility to CWD in sika deer.
Asunto(s)
Ciervos , Priones , Enfermedad Debilitante Crónica , Animales , Ciervos/genética , Endopeptidasa K/genética , Polimorfismo de Nucleótido Simple/genética , Proteínas Priónicas/genética , Priones/genética , Enfermedad Debilitante Crónica/genéticaRESUMEN
Chronic wasting disease (CWD) is a deleterious brain proteinopathy caused by a pathogenic form of prion protein (PrPSc), which is converted from a benign form of prion protein (PrPC) encoded by the prion protein gene (PRNP). In elk, the M132L single nucleotide polymorphism (SNP) of the PRNP gene likely plays a pivotal role in susceptibility to CWD. However, the association of the M132L SNP with susceptibility to CWD has not been evaluated in Korean elk to date. To estimate the association of the M132L SNP with susceptibility to CWD in Korean elk, we investigated the genotype and allele frequencies of the M132L SNP by amplicon sequencing and performed association analysis between CWD-positive and CWD-negative elk. In addition, we performed a meta-analysis to evaluate the association between the M132L SNP and susceptibility to CWD in quantitatively synthesized elk populations. Furthermore, we estimated the effect of the M132L SNP on elk PrP using in silico programs, including PolyPhen-2, PROVEAN, AMYCO and Swiss-PdbViewer. We did not identify a significant association between the M132L SNP of PRNP and susceptibility to CWD in Korean elk. The meta-analysis also did not identify a strong association between the M132L SNP of PRNP and susceptibility to CWD in quantitatively synthesized elk populations. Furthermore, we did not observe significant changes in structure, amyloid propensity or electrostatic potential based on the M132L SNP in elk PrP. To the best of our knowledge, this was the first report of an association analysis and meta-analysis in Korean elk and quantitatively synthesized elk populations, respectively.
RESUMEN
BACKGROUND: Ocular motor dysfunction is common in patients with head trauma. Also, traumatic lateral gaze palsy is usually associated with brain stem lesion, peripheral nerve injury with or without basilar skull fracture and lateral rectus muscle injury or entrapment. However, isolated bilateral abducens nerve palsy is extremely rare. CASE STUDY: This study describes a case of isolated bilateral abducens nerve palsy in a 35-year-old male with head trauma without cervical and skull fractures. He was diagnosed with mild diffuse axonal injury. During his assessment, he developed mild limb weakness, an ataxic gait and impaired abductive movement in both eyes. Angiography of the left common carotid artery revealed multiple small arteriovenous fistulae in both inferior nasal conchae. After embolization, lateral gaze palsy of his eyes was significantly improved. CONCLUSIONS: Based on this case, arteriovenous fistula should be considered as a cause of bilateral isolated abducens nerve palsy.
Asunto(s)
Enfermedades del Nervio Abducens/etiología , Fístula Arteriovenosa/complicaciones , Fístula del Seno Cavernoso de la Carótida/complicaciones , Traumatismos Craneocerebrales/complicaciones , Oftalmoplejía/etiología , Enfermedades del Nervio Abducens/fisiopatología , Accidentes de Tránsito , Adulto , Fístula Arteriovenosa/fisiopatología , Angiografía Cerebral , Traumatismos Craneocerebrales/fisiopatología , Humanos , Masculino , Oftalmoplejía/fisiopatologíaRESUMEN
Cervus canadensis nannodes (Merriam, 1905) is one of the subspecies of elk distributed only in California, USA. We completed the first mitogenome of C. canadensis nannodes. Its length is 16,428 bp, which is in middle among 24 available Cervus mitogenomes. It contains 37 genes (13 protein-coding genes, 2 rRNAs, and 22 tRNAs). Phylogenetic trees show that C. c. nannodes was clustered with some subspecies of C. elaphus. Number of inter-subspecific variations between C. c. nannodes and C. e. alxaicus are relatively small in comparison to intraspecific variations of insect and fish mitogenomes and plant chloroplast genomes.
RESUMEN
Cervus canadensis (Erxleben, 1777) has been used as a model species of Chronic Wasting Disease (CWD). We completed the mitochondrial genome of C. canadensis, susceptible to the CWD. Its length is 16,428 bp, identical to the previous mitochondrial genome of C. canadensis nannodes, and 37 genes (13 protein-coding genes, two rRNAs, and 22 tRNAs) were identified. It may reflect the extreme decrease of tule elk population in 1870s and CWD is not related to genetic elements on mitochondrial genome. Phylogenetic trees show that our mitochondrial genome is clustered with the previously sequenced mitochondrial genome of C. canadensis nannodes .
RESUMEN
Chronic wasting disease (CWD) affects a broad array of cervid species and continues to be detected in an expanding geographic range. Initially introduced into the Republic of Korea through the importation of CWD-infected elk (Cervus canadensis), additional cases of CWD were subsequently detected in farmed Korean elk and sika deer (Cervus nippon). Wild and farmed sika deer are found in many regions of Asia, North America, and Europe, although natural transmission to this species has not been detected outside of the Republic of Korea. In this study, the oral transmission of CWD to sika deer was investigated using material from CWD-affected elk. Pathological prion (PrPCWD) immunoreactivity was detected in oropharyngeal lymphoid tissues of one sika deer at 3.9 months post-inoculation (mpi) and was more widely distributed in a second sika deer examined at 10.9 mpi. The remaining four sika deer progressed to clinical disease between 21 and 24 mpi. Analysis of PrPCWD tissue distribution in clinical sika deer revealed widespread deposition in central and peripheral nervous systems, lymphoreticular tissues, and the gastrointestinal tract. Prion protein gene (PRNP) sequences of these sika deer were identical and consistent with those reported in natural sika deer populations. These findings demonstrate the efficient oral transmission of CWD from elk to sika deer.
Asunto(s)
Ciervos/fisiología , Boca/patología , Enfermedad Debilitante Crónica/transmisión , Secuencia de Aminoácidos , Animales , Proteínas Priónicas/química , Proteínas Priónicas/metabolismo , Enfermedad Debilitante Crónica/patologíaRESUMEN
African swine fever, a fatal haemorrhagic disease of swine, was confirmed in domestic pigs for the first time in South Korea in September 2019. The causative virus belonged to the p72 genotype II and had an additional tandem repeat sequence in the intergenic region (IGR) between the I73R and I329L.
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Virus de la Fiebre Porcina Africana/genética , Fiebre Porcina Africana/epidemiología , Brotes de Enfermedades/veterinaria , Fiebre Porcina Africana/virología , Animales , Femenino , Genotipo , Masculino , Filogenia , República de Corea/epidemiología , Sus scrofa , Porcinos , Secuencias Repetidas en Tándem/genéticaRESUMEN
Chronic wasting disease (CWD) agents are shed into biological samples, facilitating their horizontal transmission between cervid species. Once prions enter the environment, binding of PrPCWD by soil particles may maintain them near the soil surface, posing a challenge for decontamination. A 2 N sodium hydroxide (NaOH) or 2% sodium hypochlorite (NaClO) solution is traditionally recommended for prion decontamination of equipment and surfaces. Using protein misfolding cyclic amplification with beads and a bioassay with TgElk mice, we compared the effects of these disinfectants in CWD-contaminated soil for 1 or 16 h to those of controls of known infectious titres. Our results suggest that 2 N NaOH in a 1/5 farm soil volume provides a large decrease (>102-fold) in prion infectivity.
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Cáusticos/toxicidad , Priones/antagonistas & inhibidores , Hidróxido de Sodio/toxicidad , Suelo/química , Enfermedad Debilitante Crónica/prevención & control , Animales , Descontaminación/métodos , Ciervos/genética , Granjas , Ratones , Ratones Transgénicos , Priones/química , Priones/genética , Enfermedad Debilitante Crónica/transmisiónRESUMEN
Conformational conversion of the normal cellular isoform of the prion protein PrPC into an infectious isoform PrPSc causes pathogenesis in prion diseases. To date, numerous antiprion compounds have been developed to block this conversion and to detect the molecular mechanisms of prion inhibition using several computational studies. Thus far, no suitable drug has been identified for clinical use. For these reasons, more accurate and predictive approaches to identify novel compounds with antiprion effects are required. Here, we have applied an in silico approach that integrates our previously described pharmacophore model and fragment molecular orbital (FMO) calculations, enabling the ab initio calculation of protein-ligand complexes. The FMO-based virtual screening suggested that two natural products with antiprion activity exhibited good binding interactions, with hotspot residues within the PrPC binding site, and effectively reduced PrPSc levels in a standard scrapie cell assay. Overall, the outcome of this study will be used as a promising strategy to discover antiprion compounds. Furthermore, the SAR-by-FMO approach can provide extremely powerful tools in quickly establishing virtual SAR to prioritise compounds for synthesis in further studies.
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Productos Biológicos/uso terapéutico , Enfermedades por Prión/tratamiento farmacológico , Productos Biológicos/química , Línea Celular Tumoral , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Humanos , Simulación del Acoplamiento Molecular , Proteínas PrPSc/metabolismoRESUMEN
Enzyme-linked immunosorbent assay (ELISA) performed using extensively purified bacterially expressed bovine prion protein (PrP) shows decreased cross-reactivity. We generated a transduced Madin-Darby bovine kidney (MDBK) cell line continuously expressing glycosylphosphatidylinositol (GPI)-anchorless bovine PrP (designated as MDBK ∆GPI protein) by using a lentiviral expression system. The present study also described the method for purifying bovine PrP through sequential culturing without the need for complex purification protocol. Our results showed that the purified bovine PrP could be used as an immunogen for developing anti-PrP monoclonal antibodies. Together, our results suggest that the new GPI-anchorless bovine PrP and its purification method can be used for performing basic studies for employing a cell-based approach.
Asunto(s)
Células de Riñón Canino Madin Darby/metabolismo , Proteínas Priónicas/biosíntesis , Animales , Bovinos , Clonación Molecular , Perros , Lentivirus , Proteínas Priónicas/genética , Transducción GenéticaRESUMEN
OBJECTIVE: To investigate whether bihemispheric anodal transcranial direct current stimulation (tDCS) with conventional dysphagia therapy could improve swallowing function in chronic stroke patients with dysphagia. DESIGN: Randomized controlled trial. SUBJECTS: Twenty-six patients with dysphagia for at least 6 months post-stroke were randomly assigned into: (i) bihemispheric anodal tDCS group; or (ii) sham group. METHODS: All patients underwent 10 tDCS sessions with simultaneous conventional swallowing therapy for 2 weeks. Both anodal electrodes were attached bilaterally to the pharyngeal motor cortices, and cathodal electrodes were attached to both supraorbital regions. Swallowing function was evaluated with the Dysphagia Outcome and Severity Scale (DOSS) before and immediately after the last intervention session. RESULTS: The bihemispheric anodal tDCS group showed a mean significant improvement 0.62 points; standard deviation (SD) 0.77, in the DOSS immediately after all sessions (p = 0.02). However, there was no mean significant improvement in the sham group (0.38 points; SD 0.65(p = 0.06)). There was no significant difference between the 2 groups (p = 0.48). CONCLUSION: The bihemispheric anodal tDCS with conventional dysphagia therapy had additional helpful effects on the improvement in swallowing function in chronic stroke patients.
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Trastornos de Deglución/terapia , Rehabilitación de Accidente Cerebrovascular/métodos , Accidente Cerebrovascular/terapia , Estimulación Transcraneal de Corriente Directa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Trastornos de Deglución/fisiopatología , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Accidente Cerebrovascular/fisiopatología , Resultado del Tratamiento , Adulto JovenRESUMEN
M2B cells with persistent classical bovine spongiform encephalopathy (C-BSE) have been established previously. In this study, we performed strain characterization of the M2B cell line in bovine PrPC overexpressing mice (Tg 1896). Mice intracranially inoculated with M2B cells and C-BSE survived for 451 ± 7 and 465 ± 31 d post inoculation, respectively. Although biochemical properties, including deglycosylation and conformational stability, differed between M2B cells and C-BSE, inoculation with M2B cell lysate and C-BSE resulted in comparable phenotypes. Comparable vacuolation scores and PrPSc depositions were observed in the brain of Tg 1896 inoculated with both M2B cell lysate and C-BSE. Our results show that biochemical and biological characteristics of M2B cells and C-BSE are classifiable in the same strain.