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1.
Virus Evol ; 8(1): veac038, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35615103

RESUMEN

High throughput sequencing allowed the discovery of many new viruses and viral organizations increasing our comprehension of virus origin and evolution. Most RNA viruses are currently characterized through similarity searches of annotated virus databases. This approach limits the possibility to detect completely new virus-encoded proteins with no detectable similarities to existing ones, i.e. ORFan proteins. A strong indication of the ORFan viral origin in a metatranscriptome is the lack of DNA corresponding to an assembled RNA sequence in the biological sample. Furthermore, sequence homology among ORFans and evidence of co-occurrence of these ORFans in specific host individuals provides further indication of a viral origin. Here, we use this theoretical framework to report the finding of three conserved clades of protein-coding RNA segments without a corresponding DNA in fungi. Protein sequence and structural alignment suggest these proteins are distantly related to viral RNA-dependent RNA polymerases (RdRP). In these new putative viral RdRP clades, no GDD catalytic triad is present, but the most common putative catalytic triad is NDD and a clade with GDQ, a triad previously unreported at that site. SDD, HDD, and ADD are also represented. For most members of these three clades, we were able to associate a second genomic segment, coding for a protein of unknown function. We provisionally named this new group of viruses ormycovirus. Interestingly, all the members of one of these sub-clades (gammaormycovirus) accumulate more minus sense RNA than plus sense RNA during infection.

2.
Plant Dis ; 106(1): 275-281, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34293918

RESUMEN

Tomato brown rugose fruit virus (ToBRFV), belonging to the genus Tobamovirus, is a highly virulent emerging virus, causing disease outbreaks and significant crop losses worldwide. The growing number of ToBRFV epidemic episodes prompted the investigation of the role of seeds in the dissemination of the virus as an important aspect in the overall disease management. Therefore, the objectives of this study were to determine the localization of ToBRFV within tomato seeds and to evaluate its seed transmission characteristics. Seeds extracted from naturally ToBRFV-infected tomato fruits were tested for the presence of the virus using serological, molecular, and biological assays. Three immunolocalization techniques were used to determine the localization and distribution of ToBRFV within the different tissues and parts of tomato seeds. To evaluate seed transmission of ToBRFV, two grow-out experiments were conducted to assess the rate of both vertical (seeds to progeny seedlings) and possible horizontal transmission (plant to plant) based on serological and molecular assays. Seeds extracted from ToBRFV-infected fruits had a 100% contamination rate. The localization of ToBRFV in tomato seeds is only external on the seed coat (testa). Seed transmission rate from seeds to their seedlings was very low (0.08%), while no transmission was recorded from plants to plants in a small-scale greenhouse experimental setup. In conclusion, ToBRFV is a seedborne virus located externally on tomato seed coat and transmitted mechanically from ToBRFV-contaminated tomato seeds to seedlings, which could initiate a disease foci and eventually drive further dissemination and spread of the disease in a new growing area.


Asunto(s)
Enfermedades de las Plantas/virología , Semillas/virología , Solanum lycopersicum , Tobamovirus , Frutas , Solanum lycopersicum/virología
3.
J Virol ; 95(21): e0059721, 2021 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-34232724

RESUMEN

Frankliniella occidentalis (western flower thrips [WFT]) and Thrips tabaci (onion thrips [OT]) are insect species that greatly impact horticultural crops through direct damage and their efficient vectoring of tomato spotted wilt virus and iris yellow spot virus. In this study, we collected thrips of these species from 12 field populations in various regions in Italy. We also included one field population of Neohydatothrips variabilis (soybean thrips [ST]) from the United States. Total RNA data from high-throughput sequencing (HTS) were used to assemble the virome, and then we assigned putative viral contigs to each thrips sample by real-time reverse transcription-quantitative PCR (qRT-PCR). Excluding plant and fungal viruses, we were able to identify 61 viral segments, corresponding to 41 viruses: 14 were assigned to WFT, 17 to OT, and 1 to ST; 9 viruses could not be assigned to any species based on our stringent criteria. All these viruses are putative representative of new species (with only the exception of a sobemo-like virus that is 100% identical to a virus recently characterized in ST) and some belong to new higher-ranking taxa. These additions to the viral phylogeny suggest previously undescribed evolutionary niches. Most of Baltimore's classes of RNA viruses were present (positive- and minus-strand and double-stranded RNA viruses), but only one DNA virus was identified in our collection. Repeated sampling in a subset of locations in 2019 and 2020 and further virus characterization in a subset of four thrips populations maintained in the laboratory allowed us to provide evidence of a locally persistent thrips core virome that characterizes each population. IMPORTANCE Harnessing the insect microbiome can result in new approaches to contain their populations or the damage they cause vectoring viruses of medical, veterinary, or agricultural importance. Persistent insect viruses are a neglected component of their microbiota. In this study, for the first time, we characterize the virome associated with the two model systems for tospovirus-transmitting thrips species, of utmost importance for the direct and indirect damage they cause to a number of different crops. The thrips virome characterized includes several novel viruses, which in some cases reveal previously undescribed clades. More importantly, some of the viruses we describe are part of a core virome that is specific and consistently present in distinct geographical locations monitored over the years, hinting at a possible mutualistic symbiotic relationship with their host.


Asunto(s)
Insectos Vectores/virología , Thysanoptera/virología , Tospovirus/clasificación , Tospovirus/genética , Viroma , Animales , Biología Computacional/métodos , Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Enfermedades de las Plantas/virología , Virus ARN/clasificación , Virus ARN/genética , ARN Viral , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Especificidad de la Especie
4.
Langenbecks Arch Surg ; 406(4): 1173-1180, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33025079

RESUMEN

PURPOSE: The most frequent long-term complication after ileocecal resection in Crohn's disease is anastomotic recurrence and subsequent stenosis. Recurrence typically begins at the site of the anastomosis, raising the question of whether the surgical technique of the anastomosis could affect recurrence rates. Kono-S anastomosis is a hand-sewn antimesenteric functional end-to-end anastomosis that offers a wide lumen that is well accessible for endoscopic dilatation. The purpose of our study is to review the rate of postoperative complications almost 2 years after the introduction of this technique. MATERIALS AND METHODS: This is a prospective single-center cohort study of all consecutive patients with Crohn's disease undergoing ileocecal resection. Patients' characteristics as well as specific data for the surgical procedure and short-term outcome were evaluated. RESULTS: Thirty patients were operated for Crohn's disease of the terminal ileum (n = 24) or anastomotic recurrence (n = 6). Postoperative complications with a Clavien-Dindo Score ≥ IIIb were observed in three patients. One patient showed a hemorrhage and underwent surgical hemostasis. Two patients developed anastomotic leakage; in both cases, ileostomy was created after resection of the anastomosis. The median hospital stay was 9 days (IQR 7-12). A comparison with a historic group of conventionally operated patients of our hospital revealed no differences in short-term results except for the duration of surgery. CONCLUSION: The Kono-S anastomosis is associated with acceptable short-term results, complications, and recurrence rates comparable with the established anastomotic techniques. Longer operation times are observed, but the few published studies concerning long-term recurrence are promising.


Asunto(s)
Enfermedad de Crohn , Anastomosis Quirúrgica , Estudios de Cohortes , Enfermedad de Crohn/cirugía , Humanos , Íleon/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Recurrencia , Estudios Retrospectivos
5.
Virology ; 553: 51-61, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33221630

RESUMEN

Cryphonectria parasitica, the causal agent of chestnut blight is controlled in Europe through natural spread of Cryphonectria hypovirus 1 (CHV1), a mycovirus able to induce hypovirulence to the host. In recent years C. parasitica was reported infecting Azerbaijani population of chestnut, but the presence of CHV1 still needs to be confirmed. Aim of this work was to investigate fifty-five C. parasitica isolates collected in Azerbaijan to describe the associated viruses. Our work found i) the first negative-sense ssRNA virus known to infect C. parasitica naturally for which we propose the name Cryphonectria parasitica sclerotimonavirus 1 (CpSV1) and ii) an RNA sequence showing peculiar features suggesting a viral nature for which we propose the name Cryphonectria parasitica ambivirus 1 (CpaV1). The discovery of CpaV1 expands our knowledge of the RNA virosphere suggesting the existence of a new lineage that cannot presently be reliably associated to the monophyletic Riboviria.


Asunto(s)
Ascomicetos/virología , Virus Fúngicos/aislamiento & purificación , Mononegavirales/aislamiento & purificación , Viroma , Ascomicetos/aislamiento & purificación , Azerbaiyán , Fagaceae/microbiología , Virus Fúngicos/clasificación , Virus Fúngicos/genética , Genoma Viral , Mononegavirales/clasificación , Mononegavirales/genética , Sistemas de Lectura Abierta , Filogenia , Corteza de la Planta/microbiología , Enfermedades de las Plantas/microbiología , Proteínas Virales/química , Proteínas Virales/genética
6.
Virus Evol ; 6(2): veaa058, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33324489

RESUMEN

The obligatory biotrophic oomycetes Plasmopara viticola is the causal agent of downy mildew, a destructive disease of grapevine worldwide. So far, chemical fungicides are widely employed to limit this pathogen, but their adverse effects are stimulating the quest for environmentally friendly alternative approaches. Here, we report on the search for mycoviruses that might be later developed as biocontrol agents for this pathogen. Symptomatic leaves were collected from various regions in Spain and Italy and mycelia associated to leaf lesions was harvested. Total RNA extractions were depleted of rRNA and metatranscriptomes were generated using a high-throughput sequencing approach. The virome associated to leaf lesions was then characterized through a bioinformatic pipeline relying on blast searches against current viral databases. Here, we present an inventory of 283 new RNA viruses: 222 positive strand RNA viruses, 29 negative strand RNA viruses, 27 double-stranded RNA viruses and 5 ORFan virus RdRP segments, which could not be reliably assigned to any existing group in the Riboviria. In addition to ORFan viruses, we found other surprising new evolutionary trajectories in this wide inventory of viruses. The most represented viruses in our collection are those in phylum Lenarviricota, and, among them, a group of mycovirus segments distantly related to narnaviruses, but characterized by a polymerase palm domain lacking subdomain C, with the putative GDD catalytic triad. We also provided evidence of a strict association between two RNA segments that form a new mycovirus clade of positive strand RNA in the phylum Kitrinoviricota, order Martellivirales. In the phylum Negarnaviricota, we report for the first time in the order Mononegavirales a clade of viruses that is ambisense, a feature that so far was present only in the order Bunyavirales. Furthermore, in the same phylum we detected the widespread occurrence and abundant accumulation in our libraries of a distinct mycovirus clade distantly related to the Muvirales and Goujanvirales orders, which so far include only viruses infecting invertebrates. Possible new oomycetes-specific virus clades are also described in the phylum Duplornaviricota. These data greatly expand the evolutionary history of mycoviruses adding new layers of diversity to the realm Riboviria.

7.
Eur J Radiol ; 131: 109257, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32947092

RESUMEN

PURPOSE: To compare a zoomed EPI-DWI (z-EPI) with a standard EPI-DWI (s-EPI) in the primary diagnostics of rectal cancer and assess its potential of reduced image artifacts. METHOD: 22 therapy-naïve patients with rectal cancer underwent rectal MRI at a 3 T-system. The protocols consisted of a z-EPI DWI and s-EPI DWI sequence. Images were assessed by two independent and experienced readers regarding overall image quality and artifacts on a 5-point Likert scale, as well as overall sequence preference. In a lesion-based analysis, tumor and lymph node detection were rated on a 4-point Likert scale. Apparent diffusion coefficient (ADC) measurements were performed. RESULTS: Overall Image quality score for z-EPI and s-EPI showed no statistically significant differences (p = 0.80/0.54, reader 1/2) with a median score of 4 ("good" image quality) for both sequences. The image quality preference rank for z-EPI and s-EPI was given the category 'no preference' in 64 % (reader 1) and 50 % (reader 2). Most artifact-related scores (susceptibility, motion and distortion) did not show reproducible significant differences between z-EPI and s-EPI. The two sequences exhibited comparable, mostly good and excellent quality scores for tumor and lymph node detection (p = 0.19-0.99). ADC values were significantly lower for z-EPI than for s-EPI (p = 0.001/0.002, reader 1/2) with good agreement of ADC measurements between both readers. CONCLUSION: Our data showed comparable image quality and lesion detection for the z-EPI and the s-EPI sequence in MRI of rectal cancer, whereas the mean ADC of the tumor was significantly lower in z-EPI compared to s-EPI.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Imagen Eco-Planar/métodos , Imagenología Tridimensional/métodos , Neoplasias del Recto/diagnóstico por imagen , Adulto , Anciano , Artefactos , Femenino , Humanos , Aumento de la Imagen , Ganglios Linfáticos/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Prospectivos
8.
Arch Virol ; 165(10): 2379-2384, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32761427

RESUMEN

In this study, we determined the complete genome sequence of a new blunervirus isolated from tomato plants grown in an open field in Italy in the fall of 2018. Like other blunerviruses, the RNA genome of this virus is quadripartite, positive-sense, and single-stranded. Excluding the polyA tail present in each segment, the RNAs 1 and 2 are 5790 nucleotides (nt) and 3621 nt in size, respectively, and each contains a single open reading frame (ORF). The RNAs 3 and 4 are 2842 and 1924 nt long and encode five and two ORFs, respectively. BLASTp analysis of the predicted products of RNA1 and RNA2 ORF1 showed the highest sequence identity (31% and 42%) to tea plant necrotic ring blotch virus (TPNRBV), while the protein encoded by RNA 4 ORF2 had the highest sequence identity (38%) to blueberry necrotic ring blotch virus (BNRBV). These are the only two recognized members in the genus Blunervirus. When the RNA3 ORF3 and ORF5 products were compared with the blunerviruses-encoded proteins, they had the highest sequence identity (30% and 32%) to their TPNRBV-encoded homologs; however, general comparisons showed stronger matches to two different proteins from Acinetobacter baumannii. The proteins encoded by ORFs 1, 2 and 4 of RNA3 and ORF 1 of RNA4 showed no significant BLASTp hits to any known proteins in the databases. Given the limited genetic similarity of this virus to those currently available in the databases, we suggest that this is a new virus, for which we propose the name "tomato fruit blotch virus" (ToFBV). A distinct isolate of the same virus was also detected in Australia.


Asunto(s)
Genoma Viral , Filogenia , Virus ARN/genética , Solanum lycopersicum/virología , Proteínas Virales/genética , Australia , Secuencia de Bases , Productos Agrícolas/virología , Italia , Sistemas de Lectura Abierta , Enfermedades de las Plantas/virología , Virus ARN/clasificación , Virus ARN/aislamiento & purificación , ARN Viral/genética , Alineación de Secuencia
9.
Virus Res ; 286: 197964, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32445873

RESUMEN

Camellia japonica plants manifesting a complex and variable spectrum of viral symptoms like chlorotic ringspots, necrotic rings, yellowing with necrotic rings, yellow mottle, leaves and petals deformations, and flower color-breaking have been studied since 1940, mainly by electron microscopic analyses; however, a strong correlation between the symptoms and one or more well-characterized viruses was never verified. In this work, samples collected from symptomatic plants were analyzed using the next-generation sequencing technique, and a complex virome composed of members of the Betaflexiviridae and Fimoviridae families was identified. In particular, the genomic fragments typical of the emaravirus group were organized in the genomes of two new emaraviruses species, tentatively named Camellia japonica-associated emaravirus 1 and 2. They are the first emaraviruses described in camellia plants and found in symptomatic plants. At the same time, in both symptomatic and asymptomatic plants, five betaflexivirus isolates were detected that, based on amino acid sequence comparisons, can be considered two new isolates of the recently characterized camellia ringspot-associated virus 1 and 2 (CRSaV-1/2). These recently identified betaflexiviruses associated with C. japonica disease show an unusual hyper-conservation of the coat protein at the amino acid level. The GenBank/EMBL/DDBJ accession numbers of the sequences reported in this paper are MN385581, MN532567, MN532565, MN385582, MN532566, MN385573, MN385577, MN385574, MN385578, MN385575, MN385579, MN385576, MN385580, MN557024, MN557025, MN557026, MN557027, and MN557028.


Asunto(s)
Camellia/virología , Flexiviridae/clasificación , Genoma Viral , Enfermedades de las Plantas/virología , Virus ARN/clasificación , Viroma , Flexiviridae/aislamiento & purificación , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Hojas de la Planta/virología , Virus ARN/aislamiento & purificación
10.
Virus Res ; 273: 197737, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31479695

RESUMEN

Holothuria polii is a marine animal with an important ecological and economic impact. In the present study we analysed the presence of mycoviruses associated to fungi that were isolated from different H. polii tissues. Among the 48 fungal isolates analysed we identified 10 viruses in 8 strains belonging to 7 fungal species. Five out of nine viruses have a dsRNA genome: three of them belong to the Partitiviridae family, one belongs to a still undefined clade of bipartite viruses and the last one belongs to the Chrysoviridae family. We also identified two viruses belonging to a recently proposed new mycovirus taxon named polymycovirus. Two viruses belong to the positive single stranded RNA clade: one falls into the new Botourmiaviridae family, specifically in the Magoulivirus genus, and the other one falls into a still undefined clade phylogenetically related to tombusviruses. Finally, we also identified a virus with a negative stranded RNA genome showing similarity to a group of viruses recently proposed as a new family of mycoviruses in the order Bunyavirales. A bioinformatics approach comparing two datasets of contigs containing two closely related mycobunyaviruses allowed us to identify putative nucleocapsids (Nc) and non-structural (Ns) associated proteins. The GenBank/eMBL/DDBJ accession numbers of the sequences reported in this paper are: PRJNA432529, MG913290, MG913291, MG887747, MG887748, MG887749, MG887750, MG887751, MG887752, MG887753, MG887754, MG887755, MG887756, MG887757, MG887758, MG887759, MG887760, MG887761, MG887762, MG887763, MG887764, MG887765, MG887766, MG887767, MH271211, MN163273, MN163274.


Asunto(s)
Virus Fúngicos/clasificación , Virus Fúngicos/aislamiento & purificación , Hongos/virología , Genoma Viral , Holothuria/microbiología , Filogenia , Animales , Biología Computacional , Secuenciación de Nucleótidos de Alto Rendimiento , Virus ARN/clasificación , ARN Bicatenario , ARN Viral/genética
11.
J Virol ; 93(7)2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30651361

RESUMEN

Indirect evidence of mitochondrial viruses in plants comes from discovery of genomic fragments integrated into the nuclear and mitochondrial DNA of a number of plant species. Here, we report the existence of replicating mitochondrial virus in plants: from transcriptome sequencing (RNA-seq) data of infected Chenopodium quinoa, a plant species commonly used as a test plant in virus host range experiments, among other virus contigs, we could assemble a 2.7-kb contig that had highest similarity to mitoviruses found in plant genomes. Northern blot analyses confirmed the existence of plus- and minus-strand RNA corresponding to the mitovirus genome. No DNA corresponding to the genomic RNA was detected, excluding the endogenization of such virus. We have tested a number of C. quinoa accessions, and the virus was present in a number of commercial varieties but absent from a large collection of Bolivian and Peruvian accessions. The virus could not be transmitted mechanically or by grafting, but it is transmitted vertically through seeds at a 100% rate. Small RNA analysis of a C. quinoa line carrying the mitovirus and infected by alfalfa mosaic virus showed that the typical antiviral silencing response active against cytoplasmic viruses (21- to 22-nucleotide [nt] vsRNA peaks) is not active against CqMV1, since in this specific case the longest accumulating vsRNA length is 16 nt, which is the same as that corresponding to RNA from mitochondrial genes. This is evidence of a distinct viral RNA degradation mechanism active inside mitochondria that also may have an antiviral effect.IMPORTANCE This paper reports the first biological characterization of a bona fide plant mitovirus in an important crop, Chenopodium quinoa, providing data supporting that mitoviruses have the typical features of cryptic (persistent) plant viruses. We, for the first time, demonstrate that plant mitoviruses are associated with mitochondria in plants. In contrast to fungal mitoviruses, plant mitoviruses are not substantially affected by the antiviral silencing pathway, and the most abundant mitovirus small RNA length is 16 nt.


Asunto(s)
Chenopodium quinoa/virología , Citoplasma/virología , Virus de Plantas/genética , Virus ARN/genética , ARN Viral/genética , Genoma Viral/genética , Sistemas de Lectura Abierta/genética , Enfermedades de las Plantas/virología , Proteínas Virales/genética , Replicación Viral/genética
12.
Environ Microbiol ; 21(6): 1957-1968, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30289193

RESUMEN

To date, no demonstration of a direct correlation between the presence of mycoviruses and the quantitative or qualitative modulation of mycotoxins has been shown. In our study, we transfected a virus-free ochratoxin A (OTA)-producing isolate of Aspergillus ochraceus with purified mycoviruses from a different A. ochraceus isolate and from Penicillium aurantiogriseum. Among the mycoviruses tested, only Aspergillus ochraceus virus (AoV), a partitivirus widespread in A. ochraceus, caused a specific interaction that led to an overproduction of OTA, which is regulated by the European Commission and is the second most important contaminant of food and feed commodities. Gene expression analysis failed to reveal a specific viral upregulation of the mRNA of genes considered to play a role in the OTA biosynthetic pathway. Furthermore, AoOTApks1, a polyketide synthase gene considered essential for OTA production, is surprisingly absent in the genome of our OTA-producing isolate. The possible biological and evolutionary implications of the mycoviral regulation of mycotoxin production are discussed.


Asunto(s)
Aspergillus ochraceus/metabolismo , Aspergillus ochraceus/virología , Virus Fúngicos/fisiología , Ocratoxinas/biosíntesis , Vías Biosintéticas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Virus Fúngicos/genética , Virus Fúngicos/aislamiento & purificación , Penicillium/genética , Penicillium/metabolismo , Penicillium/virología , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo
14.
Aliment Pharmacol Ther ; 47(1): 55-66, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29052254

RESUMEN

BACKGROUND: Smoking is a strong environmental factor leading to adverse outcomes in Crohn's disease, but a more benign course in ulcerative colitis. Several single nucleotide polymorphisms (SNPs) are associated with smoking quantity and behaviour. AIM: To assess whether smoking-associated SNPs interact with smoking to influence the clinical course of inflammatory bowel diseases. METHODS: Genetic and prospectively obtained clinical data from 1434 Swiss inflammatory bowel disease cohort patients (821 Crohn's disease and 613 ulcerative colitis) were analysed. Six SNPs associated with smoking quantity and behaviour (rs588765, rs1051730, rs1329650, rs4105144, rs6474412 and rs3733829) were combined to form a risk score (range: 0-12) by adding the number of risk alleles. We calculated multivariate models for smoking, risk of surgery, fistula, Crohn's disease location and ulcerative colitis disease extent. RESULTS: In Crohn's disease patients who smoke, the number of surgeries was associated with the genetic risk score. This translates to a predicted 3.5-fold (95% confidence interval: 2.4- to 5.7-fold, P<.0001) higher number of surgical procedures in smokers with 12 risk alleles than individuals with the lowest risk. Patients with a risk score >7 had a significantly shorter time to first intestinal surgery. The genetic risk score did not predict surgery in ulcerative colitis or occurrence of fistulae in Crohn's disease. SNP rs6265 was associated with ileal disease in Crohn's disease (P<.05) and proctitis in ulcerative colitis (P<.05). CONCLUSIONS: SNPs associated with smoking quantity is associated with an increased risk for surgery in Crohn's disease patients who smoke. Our data provide an example of genetics interacting with the environment to influence the disease course of inflammatory bowel disease.


Asunto(s)
Colitis Ulcerosa/cirugía , Enfermedad de Crohn/cirugía , Fumar/epidemiología , Adulto , Alelos , Estudios de Cohortes , Colitis Ulcerosa/genética , Enfermedad de Crohn/genética , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Proctitis/epidemiología , Estudios Prospectivos , Factores de Riesgo , Fumar/efectos adversos , Adulto Joven
15.
Sci Rep ; 7(1): 1908, 2017 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-28507331

RESUMEN

So far there is no record of a specific virus able to infect both fungal and plant hosts in nature. However, experimental evidence shows that some plant virus RdRPs are able to perform replication in trans of genomic or DI RNAs in the yeast Saccharomyces cerevisiae. Furthermore, tobacco mosaic virus was recently shown to replicate in a filamentous ascomycetous fungus. Thus, at least experimentally, some plant viruses can infect some fungi. Endophytic fungi have been reported from many plants and several of these fungi have been shown to contain viruses. Here we tested if mycoviruses derived from a marine plant endophyte can replicate in plant cells. For this purpose, we used partially purified viral particles from isolate MUT4330 of Penicillium aurantiogriseum var. viridicatum which harbors six virus species, some having dsRNA and some positive-strand ssRNA genomes. These were transfected into three distinct plant protoplast cell systems. Time-course analysis of absolute RNA accumulation provided for the first time evidence that viruses of two species belonging to the Partitiviridae and Totiviridae families, can replicate in plant cells without evidence of host adaptation, i.e, changes in their nucleotide sequence.


Asunto(s)
Endófitos/virología , Virus Fúngicos/fisiología , Hongos/virología , Células Vegetales/virología , Replicación Viral , Evolución Biológica , Citoplasma/virología , Interacciones Huésped-Patógeno , Temperatura , Nicotiana/microbiología , Activación Viral
16.
Arch Virol ; 162(5): 1419-1422, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28155192

RESUMEN

The complete genome sequence of melon severe mosaic virus (MSMV), genus Tospovirus, family Bunyaviridae, was determined. The small segment is 3283 nucleotide (nt) long and contains two open reading frames in an ambisense organization. The medium segment is 4873 nt long and also encodes two proteins in an ambisense organization. The large segment is 9811 nt long and contains a single, negative-sense ORF. Phylogenetic analysis of each of the five encoded proteins compared to those of tospoviruses present in the databases reveals the same topology for each tree, suggesting that the MSMV genome did not result from recombination or reassortment. Sequence variants present in the RNA population of an infected leaf are described.


Asunto(s)
Cucumis melo/virología , Genoma Viral/genética , Virus del Mosaico/genética , Enfermedades de las Plantas/virología , ARN Viral/genética , Tospovirus/clasificación , Tospovirus/genética , Proteínas Virales/genética , Secuencia de Aminoácidos , Secuencia de Bases , Variación Genética , Sistemas de Lectura Abierta/genética , Filogenia , Hojas de la Planta/virología , Análisis de Secuencia de ARN , Tospovirus/aislamiento & purificación
18.
Tech Coloproctol ; 20(5): 293-297, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27000858

RESUMEN

BACKGROUND: Parastomal hernias (PSH) are one of the most frequent complications of enterostomies with a non-negligible complication rate and a significant socioeconomic effect. Therefore, preventing PSH by placing a mesh at the time of primary surgery has been advocated. The aim of our study was to evaluate the safety and feasibility of the new stomaplasty ring [Koring™, (Koring GmbH, Basel, Switzerland)] and investigate the reason why surgeons are reluctant to take preventive measures. METHODS: A multicenter observational study was conducted on 30 patients between December 2013 and January 2015. In permanent end colostomies and end ileostomies, the Koring™ was implanted. The primary outcome was the 30-day morbidity (infection and other stoma-related complications). Secondary endpoints were the technical feasibility and the time needed to fix the ring. In addition, an online survey of 107 surgeons was performed. RESULTS: Twenty-seven patients received permanent end colostomies, and three received end ileostomies. No stoma-related complication was detected within the first 30 days post-operatively. The Koring™ ring was evaluated by the surgeons as easy and very easy to implant in more than half of the patients. Average additional operating time for ring implantation was 19 min. CONCLUSIONS: Koring™ implantation at the time of creating the stoma is safe, easy and only adds minimally operating time. A long-term follow-up as well as a randomized controlled study is needed to evaluate the impact of the Koring™ on PSH prevention. The ease and rapidity with which Koring™ can be implanted may help surgeons to overcome their apprehension of using a preventative device.


Asunto(s)
Enterostomía/instrumentación , Hernia Ventral/cirugía , Complicaciones Posoperatorias/prevención & control , Prótesis e Implantes , Estomas Quirúrgicos/efectos adversos , Anciano , Colostomía/efectos adversos , Colostomía/instrumentación , Colostomía/métodos , Enterostomía/efectos adversos , Enterostomía/métodos , Estudios de Factibilidad , Femenino , Hernia Ventral/etiología , Humanos , Ileostomía/efectos adversos , Ileostomía/instrumentación , Ileostomía/métodos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Suiza
19.
Phytopathology ; 106(5): 500-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26756828

RESUMEN

Tomato marchitez virus (ToMarV; synonymous with Tomato apex necrosis virus) is a positive-strand RNA virus in the genus Torradovirus within the family Secoviridae. ToMarV is an emergent whitefly-transmitted virus that causes important diseases in tomato (Solanum lycopersicum) in Mexico. Here, the genome sequence of the ToMarV isolate M (ToMarV-M) was determined. We engineered full-length cDNA clones of the ToMarV-M genomic RNA (RNA1 and RNA2), separately, into a binary vector. Coinfiltration of both triggered systemic infections in Nicotiana benthamiana, tomato, and tomatillo (Physalis philadelphica) plants and recapitulated the biological activity of the wild-type virus. The viral progeny generated from tomato and tomatillo plants were transmissible by the whitefly Bemisia tabaci biotype B. Also, we assessed whether these infectious clones could be used for screening tomato cultivars for resistance to ToMarV and our results allowed us to differentiate resistant and susceptible tomato lines. We demonstrated that RNA1 of ToMarV-M is required for the replication of RNA2, and it can replicate independently of RNA2. From this, ToMarV-M RNA2 was used to express the green fluorescent protein in N. benthamiana plants, which allowed us to track cell-to-cell movement. The construction of full-length infectious cDNA clones of ToMarV-M provides an excellent tool to investigate virus-host-vector interactions and elucidate the functions of torradovirus-encoded proteins or the mechanisms of replication of torradovirus genomic RNA.


Asunto(s)
Genoma Viral , Virus ARN/fisiología , Solanum lycopersicum/virología , Animales , Proteínas Fluorescentes Verdes , Hemípteros , Enfermedades de las Plantas , Análisis de Secuencia de ARN , Replicación Viral
20.
Arch Virol ; 161(2): 503-6, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26586328

RESUMEN

In this study, we completed the whole genome sequence of a new tobamovirus isolated from tomato plants grown in greenhouses in Jordan during the spring of 2015. The 6393-nt single-stranded RNA (ssRNA) genome encodes four proteins, as do other tobamoviruses: two replication-related proteins of 126 kDa and 183 kDa, a 30-kDa movement protein (MP) and a 17.5-kDa coat protein (CP). Phylogenetic analysis showed that this virus does not group with either the tomato mosaic virus (ToMV) or the tobacco mosaic virus (TMV) clades. Instead, it stems from a branch leading to the TMV clade. Analysis of possible recombination events between this virus and representative isolates of closely related tomato-infecting tobamoviruses showed that at least one region originated by recombination. We provide evidence that we have identified a new tobamovirus, for which we propose the name "tomato brown rugose fruit virus".


Asunto(s)
Genoma Viral , ARN Viral/genética , Análisis de Secuencia de ADN , Solanum lycopersicum/virología , Tobamovirus/clasificación , Tobamovirus/aislamiento & purificación , Análisis por Conglomerados , Orden Génico , Jordania , Datos de Secuencia Molecular , Filogenia , Homología de Secuencia , Tobamovirus/genética , Proteínas Virales/genética
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