scholarly journals Development of a Molecular Tool for the Diagnosis of Leprosis, a Major Threat to Citrus Production in the Americas

Plant Disease ◽  
2003 ◽  
Vol 87 (11) ◽  
pp. 1317-1321 ◽  
Author(s):  
Eliane Cristina Locali ◽  
Juliana Freitas-Astua ◽  
Alessandra Alves de Souza ◽  
Marco Aurélio Takita ◽  
Gustavo Astua-Monge ◽  
...  
Keyword(s):  
The United States ◽  
Plant Viruses ◽  
South American ◽  
Rt Pcr ◽  
Citrus Industry ◽  
Genes Encoding ◽  
Citrus Production ◽  
Tentative Member ◽  
Polymerase Chain ◽  
Genomic Regions

Citrus leprosis virus (CiLV), a tentative member of the Rhabdoviridae family, affects citrus trees in Brazil, where it is transmitted by mites Brevipalpus spp. It also occurs in other South American countries and was recently identified in Central America. This northbound spread of CiLV is being considered a serious threat to the citrus industry of the United States. However, despite its importance, difficulties related to the biology of CiLV have hindered much of the progress regarding its accurate detection, leaving both the analyses of symptoms and electron microscopy as the only tools available. An attempt to overcome this problem was made by constructing a cDNA library from double-stranded RNA extracted from leprosis lesions of infected Citrus sinensis (sweet orange) leaves. After cloning and sequencing, specific primers were designed to amplify putative CiLV genome regions with similarity to genes encoding the movement protein and replicase of other plant viruses. RNA from infected citrus plants corresponding to different varieties and locations were amplified by reverse transcription-polymerase chain reaction (RT-PCR) using the two pairs of primers. Amplified products were purified, cloned in pGEM-T, and sequenced. The sequences confirmed the genomic regions previously associated with CiLV. The results demonstrate that RT-PCR was specific, accurate, rapid, and reliable for the detection of CiLV.

scholarly journals Limited Genetic Variability Among American Isolates of Grapevine virus E from Vitis spp.

Plant Disease ◽  
2016 ◽  
Vol 100 (1) ◽  
pp. 159-163 ◽  
Author(s):  
J. Vargas-Asencio ◽  
M. Al Rwahnih ◽  
A. Rowhani ◽  
F. Celebi-Toprak ◽  
J. R. Thompson ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
New York ◽  
Protein Gene ◽  
The United States ◽  
Nucleic Acid Binding ◽  
Grapevine Virus ◽  
Rt Pcr ◽  
Viral Cdna ◽  
Polymerase Chain ◽  
Binding Protein Gene

A survey for the presence of Grapevine virus E (GVE, genus Vitivirus, family Betaflexiviridae) in vineyards in New York and California was conducted using macroarray hybridization or reverse-transcription polymerase chain reaction (RT-PCR) assays. In New York, GVE was detected in 10 of 46 vines of Vitis labrusca, one V. riparia, and one Vitis hybrid. All GVE-infected New York vines were coinfected with Grapevine leafroll-associated virus-3. In California, GVE was detected in 8 of 417 vines of V. vinifera. All GVE-infected California vines were also coinfected by one of the leafroll-associated viruses and other vitiviruses. In order to assess the genetic diversity among GVE isolates, a viral cDNA was amplified by RT-PCR, and a 675-nucleotide region that included the 3′ terminus of the coat protein gene, a short intergenic region, and the 5′ terminus of the putative nucleic acid binding protein gene was sequenced. All 20 GVE isolates sequenced in this study were very closely related, with >98% nucleotide identity to the SA94 isolate from South Africa. These findings confirm the presence of GVE in major grape-growing regions of the United States and indicate a very low level of genetic diversity.

Torovirus detection in faecal specimens of calves and pigs in Hungary: Short communication

2002 ◽  
Vol 50 (3) ◽  
pp. 293-296 ◽  
Author(s):  
Katalin Matiz ◽  
S. Kecskeméti ◽  
I. Kiss ◽  
Keyword(s):  
Electron Microscopy ◽  
Short Communication ◽  
The United States ◽  
Aetiological Agent ◽  
Rt Pcr ◽  
Weaned Piglets ◽  
Chain Reaction ◽  
Specific Primers ◽  
Porcine Torovirus ◽  
Polymerase Chain

Bovine torovirus is an established aetiological agent of disease in cattle, while porcine torovirus has only been isolated from healthy animals. Evidence for the presence of torovirus has been described in several European countries and also in the United States. A survey was performed to detect toroviruses in Hungary by means of sampling ten swine and nine bovine herds. Rectal swabs and faecal specimens were collected from diarrhoeic calves and from weaned piglets. The samples were tested by the reverse transcription-polymerase chain reaction (RT-PCR) using torovirus-specific primers and the positive samples were further examined by electron microscopy (EM). Torovirus was detected in 4 diarrhoeic calves (out of 111) and in 10 healthy weaned pigs (out of 200 tested), representing two of the 9 calf herds and two of the 10 pig herds tested. This is the first report of exact diagnosis of torovirus in Hungary.

TURKEY CORONAVIRUS: AN UPDATED REVIEW

2015 ◽  
Vol 41 (01) ◽  
pp. 1-10 ◽  
Author(s):  
Yi-Ning Chen ◽  
Ching Ching Wu ◽  
Tsang Long Lin
Keyword(s):  
Genomic Analysis ◽  
Economic Loss ◽  
The United States ◽  
Rt Pcr ◽  
Infectious Bronchitis ◽  
Turkey Coronavirus ◽  
Cellular Immune Responses ◽  
Polymerase Chain ◽  
Cellular Immune ◽  
S Genes

Turkey coronavirus (TCoV) causes acute atrophic enteritis and uneven flock growth in turkey farms leading to economic loss. Since 1990's, turkey flocks have kept experiencing coronaviral enteritis sporadically in the United States, Canada, Europe, and Brazil. Poult enteritis and mortality syndrome (PEMS) caused by the co-infection of TCoV, astrovirus, and other viruses or bacteria resulted in significantly high mortality. Diagnosis of TCoV depends on reverse transcription polymerase chain reaction (RT-PCR), quantitative real-time PCR, immunohistochemistry (IHC), immunofluorescent antibody assay and virus isolation (VI). Genomic organization of TCoV is as follows: 5′ UTR-1a-1b-S-3a-3b-E-M-5a-5b-N-UTR 3′. Genomic analysis suggests the emergence of TCoV from infectious bronchitis virus (IBV) through the recombination of spike (S) gene. Both TCoV and IBV belong to species Avian coronavirus in genus Gammacoronavirus and have a single stranded RNA genome with a size about 27 kb. High similarity of S genes has been found between TCoV isolates in contrast to low similarity between IBV strains. TCoV infection induced strong humoral and cellular immune responses, characterized by high levels of antibody and interferon gamma. The fragment containing neutralizing epitopes in the S protein has been identified. Vaccines conferring protection against TCoV have not been developed and used in the fields but live attenuated, killed, DNA, and fowlpox virus vectored vaccines have been generated and their efficacies were evaluated. Molecular epidemiology of TCoV in recent outbreaks sheds more information on the evolution and transmission of TCoV, which will aid in developing effective vaccines or treatment to prevent, control, or eliminate TCoV infection.

scholarly journals Serological and RT-PCR surveillance for COVID-19 in an asymptomatic U.S. Army trainee population

2021 ◽  
Author(s):  
Shilpa Hakre ◽  
Aaron D Sanborn ◽  
Stephen W Krauss ◽  
Jennifer L Burns ◽  
Kenya N Jackson ◽  
...  
Keyword(s):  
Control Policy ◽  
The United States ◽  
Mitigation Measures ◽  
Rt Pcr ◽  
Training Environment ◽  
Combat Training ◽  
Current Test ◽  
Basic Combat Training ◽  
Polymerase Chain ◽  
New Recruits

Abstract Background Significant variability exists in the application of infection control policy throughout the United States (U.S.) Army initial entry training environment. To generate actionable information for the prevention of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)/coronavirus disease 2019 (COVID-19) transmission among new recruits, active enhanced surveillance was conducted for evidence of and exposure to SARS-CoV-2/COVID-19. Methods We serially tested recruits with a reverse transcriptase polymerase chain reaction (RT-PCR) COVID-19 and/or total antibody to SARS-CoV-2 tests at day 0, 14, and week 10 upon arrival for basic combat training at a location in the southern U.S. Results Among 1,403 recruits who were enrolled over a 6 week period from August 25 through October 11, 2020, 84 recruits tested positive by RT-PCR with more than half (55%, 46/84) testing positive at arrival and almost two-thirds (63%, 53/84) also testing seropositive at arrival. Similarly, among an overall 146 recruits who tested seropositive for SARS-CoV-2 during the period of observation, a majority (86%) of tested seropositive at arrival; no hospitalizations were observed among seropositive recruits and antibody response increased at week 10. Conclusions These findings suggest serological testing may complement current test-based measures and provide another tool to incorporate in COVID-19 mitigation measures among trainees in the U.S. Army.

scholarly journals Molecular Detection of Peronospora variabilis in Quinoa Seed and Phylogeny of the Quinoa Downy Mildew Pathogen in South America and the United States

2014 ◽  
Vol 104 (4) ◽  
pp. 379-386 ◽  
Author(s):  
Anna L. Testen ◽  
María del Mar Jiménez-Gasco ◽  
José B. Ochoa ◽  
Paul A. Backman
Keyword(s):  
United States ◽  
South America ◽  
Downy Mildew ◽  
Detection Method ◽  
Chenopodium Quinoa ◽  
The United States ◽  
Human Consumption ◽  
South American ◽  
Geographical Differences ◽  
Polymerase Chain

Quinoa (Chenopodium quinoa) is an important export of the Andean region, and its key disease is quinoa downy mildew, caused by Peronospora variabilis. P. variabilis oospores can be seedborne and rapid methods to detect seedborne P. variabilis have not been developed. In this research, a polymerase chain reaction (PCR)-based detection method was developed to detect seedborne P. variabilis and a sequencing-based method was used to validate the PCR-based method. P. variabilis was detected in 31 of 33 quinoa seed lots using the PCR-based method and in 32 of 33 quinoa seed lots using the sequencing-based method. Thirty-one of the quinoa seed lots tested in this study were sold for human consumption, with seed originating from six different countries. Internal transcribed spacer (ITS) and cytochrome c oxidase subunit 2 (COX2) phylogenies were examined to determine whether geographical differences occurred in P. variabilis populations originating from Ecuador, Bolivia, and the United States. No geographical differences were observed in the ITS-derived phylogeny but the COX2 phylogeny indicated that geographical differences existed between U.S. and South American samples. Both ITS and COX2 phylogenies supported the existence of a Peronospora sp., distinct from P. variabilis, that causes systemic-like downy mildew symptoms on quinoa in Ecuador. The results of these studies allow for a better understanding of P. variabilis populations in South America and identified a new causal agent for quinoa downy mildew. The PCR-based seed detection method allows for the development of P. variabilis-free quinoa seed, which may prove important for management of quinoa downy mildew.

scholarly journals First Report of Tomato infectious chlorosis virus in Tomato in Indonesia

Plant Disease ◽  
2003 ◽  
Vol 87 (7) ◽  
pp. 872-872 ◽  
Author(s):  
J. Th. J. Verhoeven ◽  
T. M. Willemen ◽  
J. W. Roenhorst ◽  
R. A. A. van der Vlugt
Keyword(s):  
The United States ◽  
Rt Pcr ◽  
First Report ◽  
Tomato Seedlings ◽  
Large Numbers ◽  
Lateral Shoots ◽  
Young Leaves ◽  
Polymerase Chain ◽  
Tomato Chlorosis Virus ◽  
Tomato Infectious Chlorosis Virus

In 2002, a breeding company submitted several samples of tomato (Lycopersicon esculentum) for diagnosis. Samples originated in Indonesia and were taken from protected and nonprotected crops. Plants exhibited severe chlorosis on fully expanded leaves, while young leaves were symptomless. Symptoms resembled those of the criniviruses Tomato chlorosis virus (ToCV) and Tomato infectious chlorosis virus (TICV). Moreover, large numbers of whiteflies, potential vectors of these viruses, had been observed at the plots with symptomatic plants. A reverse transcription-polymerase chain reaction (RT-PCR) with specific primers for TICV (1) yielded amplicons of the expected size of approximately 500 bp for all samples. One of the amplicons was sequenced (Genbank Accession No. AY221097) and revealed more than 98.9% identity to six isolates of TICV in NCBI Genbank. cDNA synthesis using the universal crinivirus primer HSP_M2-DW (5′ -TCRAARGTWCCKCCNCCRAA-3′) followed by PCR with a ToCV specific primerset (ToCV-UP 5′-TCATTAAAACTCAATGGGACCGAG-3′ and ToCV-DW 5′-GCGACGT AAATTGAAACCC-3′) was negative in all cases. Grafting of symptomatic shoots onto healthy tomato seedlings of cv. Money-maker showed transmission of the virus, as chlorosis appeared on fully expanded leaves of lateral shoots after 6 weeks. The presence of TICV in the graft-inoculated plants was confirmed by RT-PCR. Furthermore, mechanical inoculation to a range of herbaceous test plants did not evoke any virus symptoms, indicating the absence of mechanically transmissible viruses. Although other nonmechanically transmissible viruses cannot be fully excluded, the results together with the symptoms observed, indicate that TICV is the cause of the disease. TICV has been reported from Greece, Italy, Japan, Spain, and the United States, but to our knowledge, this is the first report of TICV in Indonesia. Reference: (1) A. M. Vaira et al. Phytoparasitica 30:290, 2002.

scholarly journals First Report of a Lettuce-Infecting Sequivirus in Chile

Plant Disease ◽  
2005 ◽  
Vol 89 (10) ◽  
pp. 1129-1129 ◽  
Author(s):  
R. Krause-Sakate ◽  
A. S. Jadão ◽  
A. C. Firmino ◽  
M. A. Pavan ◽  
F. M. Zerbini ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Mosaic Virus ◽  
Plant Viruses ◽  
Yellow Mosaic Virus ◽  
Mixed Infections ◽  
Replicase Gene ◽  
Rt Pcr ◽  
Chain Reaction ◽  
First Report ◽  
Polymerase Chain

Sequiviruses are isometric aphidborne plant viruses. Dandelion yellow mosaic virus (DaYMV), genus Sequivirus, was isolated from dandelion and lettuce in Europe. Lettuce mottle virus (LeMoV), a putative sequivirus, is often found in mixed infections with Lettuce mosaic virus (LMV) in Brazil (3). DaYMV, LeMoV and LMV cause similar mosaics in field-grown lettuce. Differences in biology and sequence suggest that DaYMV and LeMoV are distinct species (2). Forty-two and 101 lettuce samples with mosaic symptoms collected from two locations near Santiago during a survey of lettuce viruses in Chile in 2002 and 2003, respectively, were analyzed for the presence of LeMoV using reverse transcription polymerase chain reaction (RT-PCR). Total RNA was extracted (1) and used for RT-PCR with the specific LeMoV primers pairs Lmo3 (5′ ACATGAGCACTAGTGAGG 3′) and Lmo4 (5′ AGATAGAGCCGTCT GGCG 3′) (2). One of the 42 and three of the 101 samples produced the expected 300-bp fragment. Isometric particles of 30 nm diameter, typical of a sequivirus, were visualized by transmission electron microscopy. These samples were tested using RT-PCR for the presence of LMV and Cucumber mosaic virus (CMV), but no mixed infections were observed. One isolate, Ch36, was reamplified with the degenerate primer pairs DALE 1 (5′ GARTTCAACATGCACGCCAG 3′) and DALE 2 (5′ TTTTTCTCCCCATYCGTCAT 3′) which amplify part of the putative replicase gene (2) and produced a 563-bp fragment that was cloned on pGEM-T Easy (Promega, Madison, WI) and sequenced. The Ch36 product (EMBL Accession No. AM039965) showed 97% amino acid identity with LeMoV from Brazil, 79% with DaYMV, 72% with the sequivirus Parsnip yellow fleck virus, and 34% with the waikavirus Maize chlorotic dwarf virus. To our knowledge, this is the first report of a sequivirus in field lettuce in Chile, and although the virus was found at low incidence, this report extends the range of LeMoV to the western side of the Cordillera de Los Andes. The impact of LeMoV needs to be further analyzed in Chile, Brazil, and possibly other South American countries. References: (1) Y. D. Bertheau et al. DNA amplification by polymerase chain reaction (PCR) 1998. In: Methods for the Detection and Quantification of Erwinia carotovora subsp. atroseptica on potatoes. M. C. N. Perombelon and J. M. van der Wolff, eds. Scott. Crop Res. Inst. Occasional Publ., Dundee, 1998. (2) A. S. Jadão. Caracterização parcial e desenvolvimento de oligonucleotídeos específicos para detecção de sequivirus infectando alface. Ph.D. thesis. FCA-UNESP-Botucatu, Brazil, 2004. (3) O. Stangarlin et al. Plant Dis. 84:490, 2000.

Status Update of the Worldwide Citrus Industry

1991 ◽  
Author(s):  
Kenneth Fox
Keyword(s):  
New Technologies ◽  
Current Trend ◽  
The United States ◽  
Juice Quality ◽  
Citrus Industry ◽  
Alcohol Production ◽  
Citrus Juice ◽  
Freeze Concentration ◽  
The World ◽  
Citrus Production

The evolution of the World Citrus Processing industry is reviewed and current citrus production statistics are discussed. The world production of citrus, the Florida citrus outlook, and the Brazilian citrus outlook are reviewed in some detail giving the latest statistics. The production of FCOJ in Brazil is outlined and various innovative technologies that have been introduced by the Brazilian citrus industry are reviewed. Brazil’s introduction of the use of sugarcane bagasse, alcohol production from citrus as well as methods of fruit conveying are discussed in some detail. Changes in citrus juice markets over the last decade have caused new products to be introduced and the trend toward more fresh tasting less processed forms of commercial citrus juice is examined. The current trend towards not-from-concentrate in the United States and Japan is emphasized and analyzed. Finally new technologies such as freeze concentration, membrane concentration, production automation, juice quality enhancement technology, and by-product recovery technology are reviewed and their impact on world consumption patterns is addressed. Paper published with permission.

SARS-CoV-2 in spent dialysate from chronic peritoneal dialysis patients with COVID-19

Kidney360 ◽  
2020 ◽  
pp. 10.34067/KID.0006102020
Author(s):  
Xiaoling Wang ◽  
Amrish Patel ◽  
Lela Tisdale ◽  
Zahin Haq ◽  
Xiaoling Ye ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Nasal Swab ◽  
Early Stage ◽  
Acid Extraction ◽  
Rt Pcr ◽  
Bacteriophage Ms2 ◽  
Spent Dialysate ◽  
Polymerase Chain ◽  
Genomic Regions ◽  
Rule Out

Background To date it is unclear whether SARS-CoV-2 is present in spent dialysate from peritoneal dialysis (PD) patients with COVID-19. Our aim was to assess the presence or absence of SARS-CoV-2 in spent dialysate from chronic PD patients with confirmed diagnosis of COVID-19. Methods Spent PD dialysate samples from COVID-19 positive PD patients were collected between March and August 2020. The multiplexed real-time reverse transcriptase-polymerase chain reaction assay contained primer/probe sets specific to different SARS-CoV-2 genomic regions and to bacteriophage MS2 as internal process control for nucleic acid extraction. Demographic and clinical data were obtained from patients' electronic health records. Results A total of 26 spent PD dialysate samples were collected from 11 patients from 10 dialysis centers. Spent PD dialysate samples were collected on average 25±13 days (median 20, range 10 to 45) after onset of symptoms. The temporal distance of PD effluent collection relative to the closest positive nasal swab RT PCR was 15±11 days (median 14; range 1 to 41). All 26 PD effluent samples tested negative at three SARS-CoV-2 genomic regions. Conclusions Our findings indicate the absence of SARS-CoV-2 in spent PD dialysate collected 10 days or later after the onset of COVID-19 symptoms. We cannot rule out presence of SARS-CoV-2 in spent PD dialysate in the early stage of COVID-19.

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