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1.
Epilepsia ; 62(10): 2496-2504, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34328222

RESUMO

OBJECTIVE: Status epilepticus is a life-threatening neurological emergency. However, delay in median time to administration of second-line antiseizure medication exists. The aim of this quality improvement initiative was to decrease the average delay before fosphenytoin is administered for pediatric patients with generalized convulsive status epilepticus from 30 min (baseline data collected in 2013) to 15 min (50% reduction) by December 2015 and sustain this for 1 year. METHODS: Our team conducted an analysis of baseline data for patients with continuous generalized convulsive status epilepticus who received fosphenytoin after receiving first-line benzodiazepine treatment. Using quality improvement methodology, areas for improvement were identified and specific interventions developed and implemented. A timeline of 15 min to initiate fosphenytoin administration after failure of first-line treatment was considered reasonable and achievable as a project aim. RESULTS: A total of 199 patients were included in the dataset for the project. The database included patients aged 1 month and older. Ninety-eight percent of patients were between 1 month and 19 years of age. The gender distribution was even, with 54% of patients being White or Caucasian, 30% African American or Black, and 16% classified as "other." From January 2014 through December 2019, the average time before initiating fosphenytoin administration after failure of benzodiazepine therapy, for patients with generalized convulsive status epilepticus, decreased from 30 min (SD = 45.7) to 11.4 min (SD = 8.2, p = .043), thus reducing time to administration by 62%. SIGNIFICANCE: Quality improvement methodology can be successfully applied to decrease administration time between first- and second-line antiseizure medications for status epilepticus.


Assuntos
Melhoria de Qualidade , Estado Epiléptico , Anticonvulsivantes/efeitos adversos , Benzodiazepinas/uso terapêutico , Criança , Bases de Dados Factuais , Humanos , Estado Epiléptico/induzido quimicamente
2.
Saudi Dent J ; 33(4): 194-200, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34025081

RESUMO

OBJECTIVE: To provide information on the prevalence and clinical features of impacted third molar teeth in the South-Western region of Saudi Arabia. MATERIAL AND METHODS: In this cross-sectional study, 1200 panoramic radiographs (50% males and 50% females) were retrieved from the electronic clinical records of patients at the College of Dentistry, Jazan University from December 2014 to December 2016, and impacted third molars were evaluated. Data on clinical and radiographic presentation were analyzed. RESULTS: Overall, there were 291 (24.3%) patients with impacted third molars among 1200 radiographs. The distribution of impacted third molars according to the number of impacted teeth was as follows: one impaction in 121 (41.6%); two impactions in 90 (30.9%); three impactions in 42 (14.4%); and four impactions in 38 (13.1%) patients. There was a high prevalence of all impaction types among females (54.5%). Maxillary vertical angulation was most common (50%) followed by mandibular mesioangular angulation (48.3%). The depth of impaction in maxillary teeth was higher than in mandibular teeth. Pain was uncommon (4.5% of patients). DISCUSSION: Clinically, vertical impaction in the maxilla was present in 50% of patients because of limited posterior space, and mesioangular angulation in the mandible was present in 48% of patients because of inadequate space between the ramus and the second molar. These findings are similar to other reports. Vertical impaction of the maxillary wisdom tooth is mostly related to the discrepancy between the mesiodistal size of the tooth crown and the limited retromolar space. CONCLUSION: Noiseless presentation of an impacted third molar requires raising the population's awareness about the need for diagnosis and treatment of the problem to avoid any further complications. The study can be to guide surgical procedures. This study documented the prevalence, pattern, and clinical features of impacted third molars in South Western region of Saudi Arabia.

3.
Arch Virol ; 166(7): 2033-2036, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33900467

RESUMO

The complete nucleotide sequences of a monopartite begomovirus and an associated alphasatellite and betasatellite isolated from naturally infected okra (Abelmoschus esculentus) plants originating from Jordan were determined. The sequences of the begomovirus, alphasatellite, and betasatellites were determined to be 2,764, 1,307, and 1,354 nucleotides in length, respectively. Sequence Demarcation Tool (SDT) and phylogenetic analysis revealed that the begomovirus isolate shared the highest (99.5-99.8%) nt sequence identity with isolates of cotton leaf curl Gezira virus (CLCuGeV), a begomovirus found to exclusively infect cotton in Africa, and recently, in Asia and the Middle East. The DNA sequences of the alphasatellite and betasatellite exhibited the highest nt sequence identity (98.7-98.9% and 92.2-95.3%, respectively) to cotton leaf curl Gezira alphasatellite and cotton leaf curl Gezira betasatellite, respectively. This is the first identification of an African begomovirus, associated with DNA satellites, infecting okra in Jordan.


Assuntos
Abelmoschus/virologia , Begomovirus/genética , DNA Satélite/genética , África , Ásia , Sequência de Bases , DNA Viral/genética , Jordânia , Filogenia , Doenças das Plantas/virologia , Análise de Sequência de DNA/métodos
4.
Plant Dis ; 105(9): 2410-2417, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33599515

RESUMO

Begomoviruses infect food, fiber, and vegetable crop plants, including tomato, potato, bean, cotton, cucumber, and pumpkin, and damage many economically important crop plants worldwide. Tomato leaf curl Sudan virus (ToLCSDV) is the most widespread tomato-infecting begomovirus in Saudi Arabia. Using phage display technology, this study isolated two camel-derived nanobodies against purified ToLCSDV virions from a library of antigen-binding fragments (VHH or nanobody) of heavy-chain antibodies built from an immunized camel. The isolated nanobodies also cross-reacted with purified tomato yellow leaf curl virus virions and showed significant enzyme-linked immunosorbent assay reactivity with extracts from plants with typical begomovirus infection symptoms. The results can pave the way to developing diagnostics for begomovirus detection, design, and characterization of novel nanomaterials based on virus-like particles, in addition to nanobody-mediated begomovirus resistance in economically important crops, such as tomato, potato, and cucumber.


Assuntos
Begomovirus , Anticorpos de Domínio Único , Solanum lycopersicum , Begomovirus/genética , Filogenia , Doenças das Plantas , Anticorpos de Domínio Único/genética
5.
J Card Surg ; 35(7): 1634-1635, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32365430

RESUMO

Pyoderma gangrenosum (PG) can mimic early postoperative sternal wound infections. Steroid therapy is the only method of treatment for this condition, which recognizes the fact that steroids can lead to immunosuppression and potentially inhibit healing after major surgery.


Assuntos
Glucocorticoides/efeitos adversos , Complicações Pós-Operatórias/terapia , Pioderma Gangrenoso/terapia , Infecção da Ferida Cirúrgica/etiologia , Idoso , Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Desbridamento , Humanos , Masculino , Tratamento de Ferimentos com Pressão Negativa , Complicações Pós-Operatórias/etiologia , Esternotomia , Esterno , Cicatrização/efeitos dos fármacos
7.
Virusdisease ; 30(1): 84-94, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31143835

RESUMO

Merremia mosaic virus (MerMV), a bipartite begomovirus, was identified for the first time as a pathogen of commercial tomato plantings. Infection of tomato by MerMV caused mild leaf curling and yellow foliar mosaic symptoms. Herein, the MerMV was identified in symptomatic Merremia quinquefolia and M. aegyptia (Convolvulaceae) plants exhibiting bright yellow or yellow-green foliar mosaic symptoms, respectively. The full-length begomoviral components were amplified from total DNA isolated from two wild species of Merremia and commercial tomato plants during 1991-1998. The DNA was subjected to rolling circle amplification, restriction digestion, and DNA sequencing. The resultant 19 and 26 apparently full-length DNA-A and DNA-B components were ~ 2557 and ~ 2492 bases, respectively. The 140-base common region was 97.9% identical between DNA-A and -B components, a predictive evidence for cognate DNA-A and -B components. Although the DNA-A components were highly conserved at 96-100%, the DNA-B components diverged at ~ 89 to 100%, respectively. The overall clonal genomic features strongly suggested that MerMV lineage has been under host-selection for some time, and only recently, has undergone a host-shift, putatively, from wild convolvulaceous species to tomato (Solanaceae). Phylogenetically, MerMV grouped with other bipartite begomoviruses indigenous to the Caribbean region, with MerMV DNA-A components forming three clusters, and the DNA-B components grouped in one clade. Both clades contained only one closet relative, an isolate of MerMV from Venezuela, MerMV-VE. Biolistic inoculation of M. quinquefolia and tomato seedlings with the DNA-A and -B components of PR68 and PR80 resulted in development of symptoms like those observed in naturally-infected species, respectively.

8.
Sci Rep ; 7(1): 1834, 2017 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-28500338

RESUMO

Studies on the possible association between bacteria and oral squamous cell carcinoma (OSCC) remain inconclusive, largely due to methodological variations/limitations. The objective of this study was to characterize the species composition as well as functional potential of the bacteriome associated with OSCC. DNA obtained from 20 fresh OSCC biopsies (cases) and 20 deep-epithelium swabs (matched control subjects) was sequenced for the V1-V3 region using Illumina's 2 × 300 bp chemistry. High quality, non-chimeric merged reads were classified to species level using a prioritized BLASTN-algorithm. Downstream analyses were performed using QIIME, PICRUSt, and LEfSe. Fusobacterium nucleatum subsp. polymorphum was the most significantly overrepresented species in the tumors followed by Pseudomonas aeruginosa and Campylobacter sp. Oral taxon 44, while Streptococcus mitis, Rothia mucilaginosa and Haemophilus parainfluenzae were the most significantly abundant in the controls. Functional prediction showed that genes involved in bacterial mobility, flagellar assembly, bacterial chemotaxis and LPS synthesis were enriched in the tumors while those responsible for DNA repair and combination, purine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, ribosome biogenesis and glycolysis/gluconeogenesis were significantly associated with the controls. This is the first epidemiological evidence for association of F. nucleatum and P. aeruginosa with OSCC. Functionally, an "inflammatory bacteriome" is enriched in OSSC.


Assuntos
Carcinoma de Células Escamosas/etiologia , Infecções por Fusobacterium/complicações , Infecções por Fusobacterium/microbiologia , Fusobacterium nucleatum , Neoplasias Bucais/etiologia , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa , Adulto , Idoso , Biodiversidade , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Feminino , Fusobacterium nucleatum/classificação , Fusobacterium nucleatum/genética , Humanos , Masculino , Metagenoma , Metagenômica/métodos , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética
9.
Saudi Med J ; 38(4): 405-412, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28397948

RESUMO

OBJECTIVES: To report the prevalence and types of biopsied oral and maxillofacial lesions (OMLs) in South-Western (Jazan Province) region, , Kingdom of Saudi Arabia (KSA). Methods: This retrospective study was based on the retrieval of clinicopathological data for a period of 6 years between January 2009 and December 2014. These  data were obtained between October 2014 and June 2015 from the histopathology records of King Fahad Central Hospital, Jazan, KSA, which is the only referral center for biopsy services. Results: Out of the 32149 biopsies received, 714 (2.2%) were OMLs. The age ranged from 0 (neonatal) to 100 years, with a mean age of 46.8±23.4 and a male-to-female ratio of 1:1.3. The tongue was the most common site for OMLs and for malignant neoplasms, in particular. The most common category was malignant neoplasm (38.7%), followed by inflammatory lesions (16.5%). Oral malignancies accounted for 15.8% of all malignancies. Oral squamous cell carcinoma (OSCC) (36.1%) was the most frequent type, followed by pyogenic granuloma and mucocele (7% each). Shammah-associated OSCC and epithelial dysplasia were twice as common in females. Conclusion: The number of non-malignant OMLs was much lower than expected in comparison to oral malignancies. This difference can likely be explained by the fact that the biopsies were taken only when malignancy was suspected. The higher rate of OSCC reported from this region is attributed to shammah usage. This study emphasizes the importance of biopsy services for all OMLs and the prevention of shammah use.


Assuntos
Doenças da Boca/epidemiologia , Doenças da Boca/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Criança , Pré-Escolar , Feminino , Granuloma Piogênico/epidemiologia , Granuloma Piogênico/patologia , Promoção da Saúde , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/patologia , Mucocele/epidemiologia , Mucocele/patologia , Úlceras Orais , Prevalência , Estudos Retrospectivos , Arábia Saudita/epidemiologia
10.
J Gen Virol ; 98(2): 131-133, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28284245

RESUMO

The geminiviruses are a family of small, non-enveloped viruses with single-stranded, circular DNA genomes of 2500-5200 bases. Geminiviruses are transmitted by various types of insect (whiteflies, leafhoppers, treehoppers and aphids). Members of the genus Begomovirus are transmitted by whiteflies, those in the genera Becurtovirus, Curtovirus, Grablovirus, Mastrevirus and Turncurtovirus are transmitted by specific leafhoppers, the single member of the genus Topocuvirus is transmitted by a treehopper and one member of the genus Capulavirus is transmitted by an aphid. Geminiviruses are plant pathogens causing economically important diseases in most tropical and subtropical regions of the world. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of the Geminiviridae which is available at www.ictv.global/report/geminiviridae.


Assuntos
Geminiviridae/classificação , Doenças das Plantas/virologia , Animais , Microscopia Crioeletrônica , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , DNA Viral/química , DNA Viral/genética , Geminiviridae/genética , Geminiviridae/fisiologia , Geminiviridae/ultraestrutura , Ordem dos Genes , Genoma Viral , Insetos/virologia , Vírion/química , Vírion/genética , Vírion/ultraestrutura , Replicação Viral , Zea mays/virologia
11.
Arch Virol ; 162(6): 1819-1831, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28213872

RESUMO

Geminiviruses are plant-infecting single-stranded DNA viruses that occur in most parts of the world. Currently, there are seven genera within the family Geminiviridae (Becurtovirus, Begomovirus, Curtovirus, Eragrovirus, Mastrevirus, Topocuvirus and Turncurtovirus). The rate of discovery of new geminiviruses has increased significantly over the last decade as a result of new molecular tools and approaches (rolling-circle amplification and deep sequencing) that allow for high-throughput workflows. Here, we report the establishment of two new genera: Capulavirus, with four new species (Alfalfa leaf curl virus, Euphorbia caput-medusae latent virus, French bean severe leaf curl virus and Plantago lanceolata latent virus), and Grablovirus, with one new species (Grapevine red blotch virus). The aphid species Aphis craccivora has been shown to be a vector for Alfalfa leaf curl virus, and the treehopper species Spissistilus festinus is the likely vector of Grapevine red blotch virus. In addition, two highly divergent groups of viruses found infecting citrus and mulberry plants have been assigned to the new species Citrus chlorotic dwarf associated virus and Mulberry mosaic dwarf associated virus, respectively. These species have been left unassigned to a genus by the ICTV because their particle morphology and insect vectors are unknown.


Assuntos
Afídeos/virologia , Citrus/virologia , Geminiviridae/isolamento & purificação , Morus/virologia , Doenças das Plantas/virologia , Animais , Geminiviridae/classificação , Geminiviridae/genética , Insetos Vetores/virologia , Filogenia
12.
J Investig Clin Dent ; 8(4)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28052640

RESUMO

AIM: The aim of the present study was to analyze the prevalence of benign tumors of the orofacial region at a tertiary referral center in the south-western region of Saudi Arabia. METHODS: Cases from 2009 to 2014 were retrieved from October 2014 to June 2015 from the archives of the histopathology department of the center. Demographic and clinical details of the patients were recorded. RESULTS: Of the 714 oral and maxillofacial biopsy specimens, 78 (10.9%) were benign tumors. The mean age and range were 34.6±19.8 and 3-85 year, respectively. Sex distribution was equal. Most tumors were mesenchymal (34.6%), followed by epithelial (26.9%), odontogenic (20.5%), and salivary gland tumors (17.9%). Squamous cell papilloma (20.5%) was the most common, followed by pleomorphic adenoma (15.4%) and fibrous tumors (15.4%). CONCLUSIONS: The low prevalence of benign orofacial tumors found in this study indicates a lack of awareness of the importance of taking biopsy for such lesions. The information reported here emphasizes the need for biopsy investigation for all oral lesions to ascertain appropriate diagnosis.


Assuntos
Neoplasias Faciais/epidemiologia , Neoplasias Bucais/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Arábia Saudita/epidemiologia , Centros de Atenção Terciária , Adulto Jovem
13.
J Clin Pediatr Dent ; 40(1): 44-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26696106

RESUMO

OBJECTIVES: To assess the knowledge about teething, to evaluate the experiences of the mothers' during the teething of their youngest child and practices undertaken by them to relieve teething symptoms. STUDY DESIGN: A stratified cluster sampling technique was used to collect representative sample of school children of Jazan province (Saudi Arabia), who were provided with a questionnaire kit to be filled by their mothers. RESULTS: A total of 159 mothers participated in this study. More than four-fifths and three-fourths of the study population knew that the first primary teeth erupt at 6-7 months of age and lower central incisors are the first teeth to erupt respectively. The most prevalent signs and symptoms associated with teething as reported by the mothers were desire to bite (97.5%), fever (93%), diarrhoea (91.1%), increased salivation (79.9%), loss of appetite (77.4%) and gum irritation (71.7%). A little more than half (55.7%) of the mothers' gave their child a chilled object to bite and 42.1% bottle fed their baby at night to relieve teething pain. CONCLUSIONS: Many mothers had poor knowledge and misbeliefs about teething. There is a need to educate the mothers of Jazan province on the facts related to teething, specifically those related to teething pain relieving practices.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Mães , Erupção Dentária/fisiologia , Adolescente , Adulto , Fatores Etários , Atitude Frente a Saúde , Diarreia/fisiopatologia , Escolaridade , Características da Família , Feminino , Febre/fisiopatologia , Humanos , Incisivo/fisiologia , Renda , Lactente , Medicina Tradicional , Pessoa de Meia-Idade , Mães/educação , Arábia Saudita , Sialorreia/fisiopatologia , Classe Social , Dente Decíduo/fisiologia , Adulto Jovem
14.
J Int Soc Prev Community Dent ; 6(Suppl 3): S192-S196, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28217536

RESUMO

OBJECTIVE: To determine the amount of sugar and pH in commercially available soft drinks in Jazan, Saudi Arabia. This was further compared with their labeled values in order to inform the regulations. The effects of these drinks on teeth is reviewed. MATERIALS AND METHODS: Ten brands of popular soft drinks including 6 regular carbonated drinks and 4 energy drinks were obtained from the local markets. Their pH was determined using a pH meter. The amount of total sugar, glucose, fructose, and sucrose was estimated using high performance liquid chromatography (using Dionex ICS 5000 ion chromatography) at the Saudi Food and Drug Authority. Descriptive statistics was done to obtain the mean and standard deviation. Intergroup comparison was performed using independent t-test, and the labeled and estimated values within the group were compared with paired t-test. RESULTS: The labeled and estimated sugar in energy drinks (14.3 ± 0.48 and 15.6 ± 2.3, respectively) were higher than the carbonated drinks (11.2 ± 0.46 and 12.8 ± 0.99), which was statistically significant. In addition, there was a significant difference in the concentration of glucose in energy drinks (5.7 ± 1.7) compared to carbonated drinks (4.1 ± 1.4). The pH of these drinks ranged from 2.4 to 3.2. The differences between the estimated and labeled sugar in carbonated drinks showed statistical significance. Mild variation was observed in total sugar, glucose, fructose, and sucrose levels among different bottles of the same brand of these drinks. CONCLUSION: The low pH and high sugar content in these drinks are detrimental to dental health. Comparison of the estimated sugar with their labeled values showed variation in most of the brands. Preventive strategies should be implemented to reduce the health risks posed by these soft drinks.

15.
Genome Biol ; 16: 238, 2015 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-26556628

RESUMO

BACKGROUND: The CRISPR/Cas9 system provides bacteria and archaea with molecular immunity against invading phages and conjugative plasmids. Recently, CRISPR/Cas9 has been used for targeted genome editing in diverse eukaryotic species. RESULTS: In this study, we investigate whether the CRISPR/Cas9 system could be used in plants to confer molecular immunity against DNA viruses. We deliver sgRNAs specific for coding and non-coding sequences of tomato yellow leaf curl virus (TYLCV) into Nicotiana benthamiana plants stably overexpressing the Cas9 endonuclease, and subsequently challenge these plants with TYLCV. Our data demonstrate that the CRISPR/Cas9 system targeted TYLCV for degradation and introduced mutations at the target sequences. All tested sgRNAs exhibit interference activity, but those targeting the stem-loop sequence within the TYLCV origin of replication in the intergenic region (IR) are the most effective. N. benthamiana plants expressing CRISPR/Cas9 exhibit delayed or reduced accumulation of viral DNA, abolishing or significantly attenuating symptoms of infection. Moreover, this system could simultaneously target multiple DNA viruses. CONCLUSIONS: These data establish the efficacy of the CRISPR/Cas9 system for viral interference in plants, thereby extending the utility of this technology and opening the possibility of producing plants resistant to multiple viral infections.


Assuntos
Begomovirus/genética , Sistemas CRISPR-Cas , Doenças das Plantas/prevenção & controle , Doenças das Plantas/virologia , Proteínas Associadas a CRISPR/metabolismo , Resistência à Doença/genética , Endodesoxirribonucleases/metabolismo , Genoma Viral , Nicotiana/virologia
16.
J Oral Microbiol ; 7: 28934, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26426306

RESUMO

BACKGROUND: Usefulness of next-generation sequencing (NGS) in assessing bacteria associated with oral squamous cell carcinoma (OSCC) has been undermined by inability to classify reads to the species level. OBJECTIVE: The purpose of this study was to develop a robust algorithm for species-level classification of NGS reads from oral samples and to pilot test it for profiling bacteria within OSCC tissues. METHODS: Bacterial 16S V1-V3 libraries were prepared from three OSCC DNA samples and sequenced using 454's FLX chemistry. High-quality, well-aligned, and non-chimeric reads ≥350 bp were classified using a novel, multi-stage algorithm that involves matching reads to reference sequences in revised versions of the Human Oral Microbiome Database (HOMD), HOMD extended (HOMDEXT), and Greengene Gold (GGG) at alignment coverage and percentage identity ≥98%, followed by assignment to species level based on top hit reference sequences. Priority was given to hits in HOMD, then HOMDEXT and finally GGG. Unmatched reads were subject to operational taxonomic unit analysis. RESULTS: Nearly, 92.8% of the reads were matched to updated-HOMD 13.2, 1.83% to trusted-HOMDEXT, and 1.36% to modified-GGG. Of all matched reads, 99.6% were classified to species level. A total of 228 species-level taxa were identified, representing 11 phyla; the most abundant were Proteobacteria, Bacteroidetes, Firmicutes, Fusobacteria, and Actinobacteria. Thirty-five species-level taxa were detected in all samples. On average, Prevotella oris, Neisseria flava, Neisseria flavescens/subflava, Fusobacterium nucleatum ss polymorphum, Aggregatibacter segnis, Streptococcus mitis, and Fusobacterium periodontium were the most abundant. Bacteroides fragilis, a species rarely isolated from the oral cavity, was detected in two samples. CONCLUSION: This multi-stage algorithm maximizes the fraction of reads classified to the species level while ensuring reliable classification by giving priority to the human, oral reference set. Applying the algorithm to OSCC samples revealed high diversity. In addition to oral taxa, a number of human, non-oral taxa were also identified, some of which are rarely detected in the oral cavity.

17.
Arch Virol ; 160(6): 1593-619, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25894478

RESUMO

Viruses of the genus Begomovirus (family Geminiviridae) are emergent pathogens of crops throughout the tropical and subtropical regions of the world. By virtue of having a small DNA genome that is easily cloned, and due to the recent innovations in cloning and low-cost sequencing, there has been a dramatic increase in the number of available begomovirus genome sequences. Even so, most of the available sequences have been obtained from cultivated plants and are likely a small and phylogenetically unrepresentative sample of begomovirus diversity, a factor constraining taxonomic decisions such as the establishment of operationally useful species demarcation criteria. In addition, problems in assigning new viruses to established species have highlighted shortcomings in the previously recommended mechanism of species demarcation. Based on the analysis of 3,123 full-length begomovirus genome (or DNA-A component) sequences available in public databases as of December 2012, a set of revised guidelines for the classification and nomenclature of begomoviruses are proposed. The guidelines primarily consider a) genus-level biological characteristics and b) results obtained using a standardized classification tool, Sequence Demarcation Tool, which performs pairwise sequence alignments and identity calculations. These guidelines are consistent with the recently published recommendations for the genera Mastrevirus and Curtovirus of the family Geminiviridae. Genome-wide pairwise identities of 91 % and 94 % are proposed as the demarcation threshold for begomoviruses belonging to different species and strains, respectively. Procedures and guidelines are outlined for resolving conflicts that may arise when assigning species and strains to categories wherever the pairwise identity falls on or very near the demarcation threshold value.


Assuntos
Begomovirus/classificação , Begomovirus/genética , Genoma Viral/genética , Filogenia , Doenças das Plantas/virologia , Plantas/virologia , Alinhamento de Sequência
18.
Virol J ; 11: 103, 2014 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-24890736

RESUMO

BACKGROUND: Tomato leaf curl Sudan virus (ToLCSDV) is a single-stranded DNA begomovirus of tomato that causes downward leaf curl, yellowing, and stunting. Leaf curl disease results in significant yield reduction in tomato crops in the Nile Basin. ToLCSDV symptoms resemble those caused by Tomato yellow leaf curl virus, a distinct and widespread begomovirus originating in the Middle East. In this study, tomato samples exhibiting leaf curl symptoms were collected from Gezira, Sudan. The associated viral genome was molecularly characterized, analyzed phylogenetically, and an infectious clone for one isolate was constructed. FINDINGS: The complete genomes for five newly discovered variants of ToLCSDV, ranging in size from 2765 to 2767-bp, were cloned and sequenced, and subjected to pairwise and phylogenetic analyses. Pairwise analysis indicated that the five Gezira isolates shared 97-100% nucleotide identity with each other. Further, these variants of ToLCSDV shared their highest nucleotide identity at 96-98%, 91-95%, 91-92%, and 91-92% with the Shambat, Gezira, Oman and Yemen strains of ToLCSDV, respectively. Based on the high maximum nucleotide identities shared between these ToLCSDV variants from Gezira and other previously recognized members of this taxonomic group, they are considered isolates of the Shambat strain of ToLCSDV. Analysis of the complete genome sequence for these new variants revealed that they were naturally occurring recombinants between two previously reported strains of ToLCSDV. Finally, a dimeric clone constructed from one representative ToLCSV genome from Gezira was shown to be infectious following inoculation to tomato and N. benthamiana plants. CONCLUSION: Five new, naturally occurring recombinant begomovirus variants (>96% shared nt identity) were identified in tomato plants from Gezira in Sudan, and shown to be isolates of the Shambat strain of ToLCSDV. The cloned viral genome was infectious in N. benthamiana and tomato plants, and symptoms in tomato closely resembled those observed in field infected tomato plants, indicating the virus is the causal agent of the leaf curl disease. The symptoms that developed in tomato seedlings closely resembled those observed in field infected tomato plants, indicating that ToLCSDV is the causal agent of the leaf curl disease in Gezira.


Assuntos
Begomovirus/classificação , Vírus de DNA/genética , DNA Viral/genética , Genoma Viral , Doenças das Plantas/virologia , Recombinação Genética , Solanum lycopersicum/virologia , Begomovirus/genética , Begomovirus/isolamento & purificação , Análise por Conglomerados , Vírus de DNA/isolamento & purificação , DNA Viral/química , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência , Sudão
19.
Viruses ; 6(3): 1219-36, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24625811

RESUMO

Traditional DNA sequencing methods are inefficient, lack the ability to discern the least abundant viral sequences, and ineffective for determining the extent of variability in viral populations. Here, populations of single-stranded DNA plant begomoviral genomes and their associated beta- and alpha-satellite molecules (virus-satellite complexes) (genus, Begomovirus; family, Geminiviridae) were enriched from total nucleic acids isolated from symptomatic, field-infected plants, using rolling circle amplification (RCA). Enriched virus-satellite complexes were subjected to Illumina-Next Generation Sequencing (NGS). CASAVA and SeqMan NGen programs were implemented, respectively, for quality control and for de novo and reference-guided contig assembly of viral-satellite sequences. The authenticity of the begomoviral sequences, and the reproducibility of the Illumina-NGS approach for begomoviral deep sequencing projects, were validated by comparing NGS results with those obtained using traditional molecular cloning and Sanger sequencing of viral components and satellite DNAs, also enriched by RCA or amplified by polymerase chain reaction. As the use of NGS approaches, together with advances in software development, make possible deep sequence coverage at a lower cost; the approach described herein will streamline the exploration of begomovirus diversity and population structure from naturally infected plants, irrespective of viral abundance. This is the first report of the implementation of Illumina-NGS to explore the diversity and identify begomoviral-satellite SNPs directly from plants naturally-infected with begomoviruses under field conditions.


Assuntos
Begomovirus/classificação , Begomovirus/genética , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Metagenômica/métodos , Doenças das Plantas/virologia , Plantas/virologia , Begomovirus/química , DNA Satélite/química , DNA Satélite/classificação , DNA Satélite/genética , Dados de Sequência Molecular
20.
Arch Virol ; 159(8): 2193-203, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24658781

RESUMO

The family Geminiviridae includes plant-infecting circular single-stranded DNA viruses that have geminate particle morphology. Members of this family infect both monocotyledonous and dicotyledonous plants and have a nearly global distribution. With the advent of new molecular tools and low-cost sequencing, there has been a significant increase in the discovery of new geminiviruses in various cultivated and non-cultivated plants. In this communication, we highlight the establishment of three new genera (Becurtovirus, Eragrovirus and Turncurtovirus) to accommodate various recently discovered geminiviruses that are highly divergent and, in some cases, have unique genome architectures. The genus Becurtovirus has two viral species, Beet curly top Iran virus (28 isolates; leafhopper vector Circulifer haematoceps) and Spinach curly top Arizona virus (1 isolate; unknown vector), whereas the genera Eragrovirus and Turncurtovirus each have a single assigned species: Eragrostis curvula streak virus (6 isolates; unknown vector) and Turnip curly top virus (20 isolates; leafhopper vector Circulifer haematoceps), respectively. Based on analysis of all of the genome sequences available in public databases for each of the three new genera, we provide guidelines and protocols for species and strain classification within these three new genera.


Assuntos
Geminiviridae/classificação , Doenças das Plantas/virologia , Plantas/virologia , Geminiviridae/genética , Geminiviridae/isolamento & purificação , Genoma Viral , Dados de Sequência Molecular , Filogenia
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