scholarly journals EVALUATION OF THE SENSITIVITY OF NITROCELLULOSE MEMBRANE LOW-COST ALTERNATIVES USED IN TISSUE BLOT IMMUNOASSAY (TBIA) FOR DETECTION OF SOME PLANT VIRUSES

2020 ◽  
Vol 10 (1) ◽  
pp. 68-72
Author(s):  
Maha Kawanna
Keyword(s):  
Low Cost ◽  
Plant Viruses ◽  
Nitrocellulose Membrane ◽  
Tissue Blot Immunoassay

scholarly journals A Microfluidic Diagnostic Device Capable of Autonomous Sample Mixing and Dispensing for the Simultaneous Genetic Detection of Multiple Plant Viruses

Micromachines ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 540 ◽  
Author(s):  
Daigo Natsuhara ◽  
Keisuke Takishita ◽  
Kisuke Tanaka ◽  
Azusa Kage ◽  
Ryoji Suzuki ◽  
...  
Keyword(s):  
Insect Pests ◽  
Low Cost ◽  
Simultaneous Detection ◽  
Genetic Diagnosis ◽  
Plant Viruses ◽  
Plant Diseases ◽  
Lamp Method ◽  
Diagnostic Device ◽  
Tomato Crop ◽  
Computational Analyses

As an efficient approach to risk management in agriculture, the elimination of losses due to plant diseases and insect pests is one of the most important and urgent technological challenges for improving the crop yield. Therefore, we have developed a polydimethylsiloxane (PDMS)-based microfluidic device for the multiplex genetic diagnosis of plant diseases and pests. It offers unique features, such as rapid detection, portability, simplicity, and the low-cost genetic diagnosis of a wide variety of plant viruses. In this study, to realize such a diagnostic device, we developed a method for the autonomous dispensing of fluid into a microchamber array, which was integrated with a set of three passive stop valves with different burst pressures (referred to as phaseguides) to facilitate precise fluid handling. Additionally, we estimated the mixing efficiencies of several types of passive mixers (referred to as chaotic mixers), which were integrated into a microchannel, through experimental and computational analyses. We first demonstrated the ability of the fabricated diagnostic devices to detect DNA-based plant viruses from an infected tomato crop based on the loop-mediated isothermal amplification (LAMP) method. Moreover, we demonstrated the simultaneous detection of RNA-based plant viruses, which can infect cucurbits, by using the reverse transcription LAMP (RT-LAMP) method. The multiplex RT-LAMP assays revealed that multiple RNA viruses extracted from diseased cucumber leaves were successfully detected within 60 min, without any cross-contamination between reaction microchambers, on our diagnostic device.

scholarly journals Prereaction of Citrus tristeza virus (CTV) Specific Antibodies and Labeled Secondary Antibodies Increases Speed of Direct Tissue Blot Immunoassay for CTV

Plant Disease ◽  
2006 ◽  
Vol 90 (5) ◽  
pp. 675-679 ◽  
Author(s):  
Youjian Lin ◽  
Phyllis A. Rundell ◽  
Lianhui Xie ◽  
Charles A. Powell
Keyword(s):  
Citrus Tristeza Virus ◽  
Plant Viruses ◽  
Specific Antibodies ◽  
Rabbit Igg ◽  
Tissue Blot Immunoassay ◽  
Polymerase Chain ◽  
Bacteria And Fungi ◽  
Secondary Antibodies ◽  
Tristeza Virus ◽  
Citrus Tristeza

An improved direct tissue blot immunoassay (DTBIA) procedure for detection of Citrus tristeza virus (CTV) within 1 h is described. Prints of fresh young stems of citrus plants that were infected or not infected with CTV were made by gently and evenly pressing the fresh-cut surface of the stems onto a nitrocellulose membrane. The tissue blots were air-dried for 5 min, incubated with prereaction solutions of CTV-specific antibodies and labeled secondary antibodies, goat anti-mouse Ig (H+L)-alkaline phosphatase conjugate or goat anti-rabbit IgG alkaline phos-phatase conjugate, for up to 20 min, rinsed with PBST buffer for 5 min, and immersed into an NBT-BCIP substrate solution for 15 to 20 min. Then the blots were rinsed in water for a few seconds to stop the reactions, and the results were observed and recorded under a light microscope. All samples from greenhouse plants that were infected with CTV decline inducing isolate T-36 were positive to CTV-specific polyclonal antibody 1212 (PCA 1212) and monoclonal antibodies 17G11 (MAb 17G11) and MCA13 (MAb MCA13), whereas samples from greenhouse plants infected with non-decline-inducing isolate T-30 were positive to PCA 1212 and MAb 17G11, but not to MAb MCA13. The noninfected greenhouse plants were negative to all of the antibodies. The improved DTBIA was at least as reliable as other immunological procedures and almost as reliable as polymerase chain reaction for detecting CTV in field trees. The improved DTBIA enables the detection of CTV within 1 h by having a prereaction of CTV-specific antibodies and labeled secondary antibodies in solutions before they are applied to the tissue blots. This DTBIA procedure may be useful in detecting other plant viruses and other pathogens such as bacteria and fungi.

scholarly journals A Simple, Low Cost, Sensitive, and Portable Electrochemical Immunochromatography Sensing Device to Measure Estrone-3-Sulfate

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4781
Author(s):  
Wataru Iwasaki ◽  
Chiwa Kataoka ◽  
Kazuyuki Sawadaishi ◽  
Keitaro Suyama ◽  
Nobutomo Morita ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Limit Of Detection ◽  
Point Of Care ◽  
Low Cost ◽  
Electrochemical Techniques ◽  
Low Molecular Weight ◽  
Nitrocellulose Membrane ◽  
Electrochemical Detector ◽  
Simple Method ◽  
Endogenous Steroids

In livestock production, point-of-care testing (POCT) technology that enables easy on-site analysis of sex hormones is desired to improve reproductive efficiency. In this context, low-molecular-weight endogenous steroids are particularly important for perinatal management. Therefore, we attempted to use a simple method that combines electrochemical techniques with immunochromatography to measure estrone-3-sulfate (E1S), one of the low-molecular-weight endogenous steroids that is an estrogen ester. The limit of detection (LOD) for E1S achieved by electrochemical immunochromatography was 570.5 ng/mL, which was one to two orders of magnitude lower than that of small molecule compounds analyzed by other POCT techniques (Primpray et al., Anal. Chim. Acta, 2019). In addition, it was indicated by a colorimetric analysis that the sensitivity of the electrochemical immunochromatographic technique could be enhanced by improving the method of application of the antibodies on the nitrocellulose membrane and the contact between the electrochemical detector and the nitrocellulose membrane.

Plant-produced Recombinant Influenza A Vaccines Based on the M2e Peptide

2018 ◽  
Vol 24 (12) ◽  
pp. 1317-1324 ◽  
Author(s):  
Eugenia S. Mardanova ◽  
Nikolai V. Ravin
Keyword(s):  
Influenza Vaccine ◽  
Influenza A ◽  
Large Scale ◽  
Transmembrane Protein ◽  
Low Cost ◽  
Plant Viruses ◽  
Recombinant Vaccines ◽  
Scale Production ◽  
Expression Systems ◽  
Major Surface

Background: Influenza is a widely distributed infection that almost annually causes seasonal epidemics. The current egg-based platforms for influenza vaccine production are facing a number of challenges and are failing to satisfy the global demand in the case of pandemics due to the long production time. Recombinant vaccines are an alternative that can be quickly produced in high quantities in standard expression systems. Methods: : Plants may become a promising biofactory for the large-scale production of recombinant proteins due to low cost, scalability, and safety. Plant-based expression systems have been used to produce recombinant vaccines against influenza based on two targets; the major surface antigen hemagglutinin and the transmembrane protein M2. <P> Results: Different forms of recombinant hemagglutinin were successfully expressed in plants, and some plantproduced vaccines based on hemagglutinin were successfully tested in clinical trials. However, these vaccines remain strain specific, while the highly conserved extracellular domain of the M2 protein (M2e) could be used for the development of a universal influenza vaccine. In this review, the state of the art in developing plant-produced influenza vaccines based on M2e is presented and placed in perspective. A number of strategies to produce M2e in an immunogenic form in plants have been reported, including its presentation on the surface of plant viruses or virus-like particles formed by capsid proteins, linkage to bacterial flagellin, and targeting to protein bodies. Conclusion: Some M2e-based vaccine candidates were produced at high levels (up to 1 mg/g of fresh plant tissue) and were shown to be capable of stimulating broad-range protective immunity.

scholarly journals LAMP-Coupled CRISPR–Cas12a Module for Rapid and Sensitive Detection of Plant DNA Viruses

Viruses ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 466
Author(s):  
Ahmed Mahas ◽  
Norhan Hassan ◽  
Rashid Aman ◽  
Tin Marsic ◽  
Qiaochu Wang ◽  
...  
Keyword(s):  
Low Cost ◽  
Virus Detection ◽  
High Sensitivity ◽  
Plant Viruses ◽  
Economic Losses ◽  
New Delhi ◽  
Dna Viruses ◽  
Point Of Use ◽  
Tomato Leaf Curl ◽  
Leaf Curl

One important factor for successful disease management is the ability to rapidly and accurately identify the causal agent. Plant viruses cause severe economic losses and pose a serious threat to sustainable agriculture. Therefore, optimization of the speed, sensitivity, feasibility, portability, and accuracy of virus detection is urgently needed. Here, we developed a clustered regularly interspaced short palindromic repeats (CRISPR)-based nucleic acid diagnostic method utilizing the CRISPR–Cas12a system for detecting two geminiviruses, tomato yellow leaf curl virus (TYLCV) and tomato leaf curl New Delhi virus (ToLCNDV), which have single-stranded DNA genomes. Our assay detected TYLCV and ToLCNDV in infected plants with high sensitivity and specificity. Our newly developed assay can be performed in ~1 h and provides easy-to-interpret visual readouts using a simple, low-cost fluorescence visualizer, making it suitable for point-of-use applications.

Decomposition of the metastable beta titanium alloy Ti-15-3

1983 ◽  
Vol 41 ◽  
pp. 264-265
Author(s):  
Y. L. Chen ◽  
S. Fujlshiro
Keyword(s):  
Low Cost ◽  
High Strength ◽  
Alpha Phase ◽  
Thick Sheet ◽  
Omega Phase ◽  
Beta Titanium Alloy ◽  
Beta Titanium ◽  
Beta Matrix ◽  
Metastable Beta ◽  
Very High

Metastable beta titanium alloys have been known to have numerous advantages such as cold formability, high strength, good fracture resistance, deep hardenability, and cost effectiveness. Very high strength is obtainable by precipitation of the hexagonal alpha phase in a bcc beta matrix in these alloys. Precipitation hardening in the metastable beta alloys may also result from the formation of transition phases such as omega phase. Ti-15-3 (Ti-15V- 3Cr-3Al-3Sn) has been developed recently by TIMET and USAF for low cost sheet metal applications. The purpose of the present study was to examine the aging characteristics in this alloy.The composition of the as-received material is: 14.7 V, 3.14 Cr, 3.05 Al, 2.26 Sn, and 0.145 Fe. The beta transus temperature as determined by optical metallographic method was about 770°C. Specimen coupons were prepared from a mill-annealed 1.2 mm thick sheet, and solution treated at 827°C for 2 hr in argon, then water quenched. Aging was also done in argon at temperatures ranging from 316 to 616°C for various times.

Chromic Acid Etching of Polyethylene

1973 ◽  
Vol 31 ◽  
pp. 72-73
Author(s):  
J. D. Muzzy ◽  
R. D. Hester ◽  
J. L. Hubbard
Keyword(s):  
Chromic Acid ◽  
Low Cost ◽  
Acid Etching ◽  
Crystalline Morphology ◽  
Bulk Specimen ◽  
Morphological Studies ◽  
Perfect Form ◽  
Molecular Length ◽  
Lamellar Texture ◽  
Cost Studies

Polyethylene is one of the most important plastics produced today because of its good physical properties, ease of fabrication and low cost. Studies to improve the properties of polyethylene are leading to an understanding of its crystalline morphology. Polyethylene crystallized by evaporation from dilute solutions consists of thin crystals called lamellae. The polyethylene molecules are parallel to the thickness of the lamellae and are folded since the thickness of the lamellae is much less than the molecular length. This lamellar texture persists in less perfect form in polyethylene crystallized from the melt.Morphological studies of melt crystallized polyethylene have been limited due to the difficulty of isolating the microstructure from the bulk specimen without destroying or deforming it.

Ectodesmata as Revealed By Freeze-Etch Preparations of Plant Epidermal Cell Walls

1973 ◽  
Vol 31 ◽  
pp. 468-469
Author(s):  
N.C. Lyon ◽  
W. C. Mueller
Keyword(s):  
Electron Microscopy ◽  
Acetic Acid ◽  
Nitric Acid ◽  
Oxalic Acid ◽  
Light Microscopy ◽  
Epidermal Cell ◽  
Cell Walls ◽  
Plant Viruses ◽  
Plant Leaves ◽  
Thin Sections

Schumacher and Halbsguth first demonstrated ectodesmata as pores or channels in the epidermal cell walls in haustoria of Cuscuta odorata L. by light microscopy in tissues fixed in a sublimate fixative (30% ethyl alcohol, 30 ml:glacial acetic acid, 10 ml: 65% nitric acid, 1 ml: 40% formaldehyde, 5 ml: oxalic acid, 2 g: mecuric chloride to saturation 2-3 g). Other workers have published electron micrographs of structures transversing the outer epidermal cell in thin sections of plant leaves that have been interpreted as ectodesmata. Such structures are evident following treatment with Hg++ or Ag+ salts and are only rarely observed by electron microscopy. If ectodesmata exist without such treatment, and are not artefacts, they would afford natural pathways of entry for applied foliar solutions and plant viruses.

Glass Knife Geometry as Seen by the SEM

1971 ◽  
Vol 29 ◽  
pp. 454-455
Author(s):  
J. Temple Black
Keyword(s):  
Low Cost ◽  
Amorphous Material ◽  
Stress Concentrations ◽  
Basic Tool ◽  
Tool Materials ◽  
Optical Inspection ◽  
Surface Flaws ◽  
Slip Planes ◽  
Glass Knife ◽  
Diamond Knife

In ultramicrotomy, the two basic tool materials are glass and diamond. Glass because of its low cost and ease of manufacture of the knife itself is still widely used despite the superiority of diamond knives in many applications. Both kinds of knives produce plastic deformation in the microtomed section due to the nature of the cutting process and microscopic chips in the edge of the knife. Because glass has no well defined slip planes in its structure (it's an amorphous material), it is very strong and essentially never fails in compression. However, surface flaws produce stress concentrations which reduce the strength of glass to 10,000 to 20,000 psi from its theoretical or flaw free values of 1 to 2 million psi. While the microchips in the edge of the glass or diamond knife are generally too small to be observed in the SEM, the second common type of defect can be identified. This is the striations (also termed the check marks or feathers) which are always present over the entire edge of a glass knife regardless of whether or not they are visable under optical inspection. These steps in the cutting edge can be observed in the SEM by proper preparation of carefully broken knives and orientation of the knife, with respect to the scanning beam.

Sign in / Sign up

Export Citation Format

Share Document