Photobiont selectivity in the epiphytic lichens Hypogymnia physodes and Lecanora conizaeoides

2007 ◽  
Vol 39 (2) ◽  
pp. 195-204 ◽  
Author(s):  
Markus HAUCK ◽  
Gert HELMS ◽  
Thomas FRIEDL
Keyword(s):  
High Sensitivity ◽  
High Specificity ◽  
Common Type ◽  
Lichen Species ◽  
Model Organisms ◽  
Epiphytic Lichens ◽  
Hypogymnia Physodes ◽  
Lichen Symbiosis ◽  
Key Factor ◽  
Nuclear Its

Abstract:In two lichen species, Hypogymnia physodes and Lecanora conizaeoides, often used as model organisms for pollution-sensitive and pollution-tolerant epiphytic lichens, respectively, the hypothesis was tested that the toxitolerance of the Trebouxia photobiont limits the tolerance of the entire lichen symbiosis. Being lecanoralean-trebouxioid associations, H. physodes and L. conizaeoides represent the most common type of lichens. Photobionts of both lichen species deriving from microhabitats with varying supply of S and heavy metals were identified using nuclear ITS nrDNA sequencing. The photobiont of L. conizaeoides was identified as T. simplex, whereas the photobiont of H. physodes belongs to an undescribed Trebouxia species, related to T. jamesii subsp. angustilobata and provisionally named as T. hypogymniae Hauck & Friedl ined. Since T. hypogymniae ined. is also known from Lecidea silacea, which is characteristic of rock and slag with high heavy metal content, a high sensitivity of this alga to pollutants is unlikely to be a key factor for the relatively low toxitolerance of H. physodes. Furthermore, the photobiont cannot be crucial for the extremely high toxitolerance of L. conizaeoides, as T. simplex is also known from pollution-sensitive lichens of the fruticose genus Pseudevernia. These findings suggest that the photobiont is not generally a key factor determining pollution sensitivity in the most common type of lichen symbiosis. The high specificity for T. simplex in L. conizaeoides in existing populations of L. conizaeoides suggest that already established thalli could be a source of photobiont cells for re-lichenization.

scholarly journals BFG-PCA: tools and resources that expand the potential for binary protein interaction discovery

2021 ◽  
Author(s):  
Daniel Evans-Yamamoto ◽  
François D Rouleau ◽  
Piyush Nanda ◽  
Koji Makanae ◽  
Yin Liu ◽  
...  
Keyword(s):  
Protein Interaction ◽  
High Sensitivity ◽  
High Specificity ◽  
Model Organisms ◽  
Protein Protein Interaction ◽  
Test Protein ◽  
Protein Fragment Complementation ◽  
Yeast Interactions ◽  
Protein Fragment Complementation Assay

Barcode fusion genetics (BFG) utilizes deep sequencing to improve the throughput of protein-protein interaction (PPI) screening in pools. BFG has been implemented in Yeast two-hybrid (Y2H) screens (BFG-Y2H). While Y2H requires test protein pairs to localize in the nucleus for reporter reconstruction, Dihydrofolate Reductase Protein-Fragment Complementation Assay (DHFR-PCA) allows proteins to localize in broader subcellular contexts and proves to be largely orthogonal to Y2H. Here, we implemented BFG to DHFR-PCA (BFG-PCA). This plasmid-based system can leverage ORF collections across model organisms to perform comparative analysis, unlike the original DHFR-PCA that requires yeast genomic integration. The scalability and quality of BFG-PCA were demonstrated by screening human and yeast interactions of >11,000 protein pairs. BFG-PCA showed high-sensitivity and high-specificity for capturing known interactions for both species. BFG-Y2H and BFG-PCA capture distinct sets of PPIs, which can partially be explained based on the domain orientation of the reporter tags. BFG-PCA is a high-throughput protein interaction technology to interrogate binary PPIs that exploits clone collections from any species of interest, expanding the scope of PPI assays.

scholarly journals Radiochemistry, Production Processes, Labeling Methods, and ImmunoPET Imaging Pharmaceuticals of Iodine-124

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 414
Author(s):  
Krishan Kumar ◽  
Arijit Ghosh
Keyword(s):  
Physical Properties ◽  
Imaging Modality ◽  
Target Selection ◽  
Positron Emission Tomography Imaging ◽  
High Sensitivity ◽  
High Specificity ◽  
Production Processes ◽  
Positron Emission ◽  
Significant Research ◽  
Clinical Environments

Target-specific biomolecules, monoclonal antibodies (mAb), proteins, and protein fragments are known to have high specificity and affinity for receptors associated with tumors and other pathological conditions. However, the large biomolecules have relatively intermediate to long circulation half-lives (>day) and tumor localization times. Combining superior target specificity of mAbs and high sensitivity and resolution of the PET (Positron Emission Tomography) imaging technique has created a paradigm-shifting imaging modality, ImmunoPET. In addition to metallic PET radionuclides, 124I is an attractive radionuclide for radiolabeling of mAbs as potential immunoPET imaging pharmaceuticals due to its physical properties (decay characteristics and half-life), easy and routine production by cyclotrons, and well-established methodologies for radioiodination. The objective of this report is to provide a comprehensive review of the physical properties of iodine and iodine radionuclides, production processes of 124I, various 124I-labeling methodologies for large biomolecules, mAbs, and the development of 124I-labeled immunoPET imaging pharmaceuticals for various cancer targets in preclinical and clinical environments. A summary of several production processes, including 123Te(d,n)124I, 124Te(d,2n)124I, 121Sb(α,n)124I, 123Sb(α,3n)124I, 123Sb(3He,2n)124I, natSb(α, xn)124I, natSb(3He,n)124I reactions, a detailed overview of the 124Te(p,n)124I reaction (including target selection, preparation, processing, and recovery of 124I), and a fully automated process that can be scaled up for GMP (Good Manufacturing Practices) production of large quantities of 124I is provided. Direct, using inorganic and organic oxidizing agents and enzyme catalysis, and indirect, using prosthetic groups, 124I-labeling techniques have been discussed. Significant research has been conducted, in more than the last two decades, in the development of 124I-labeled immunoPET imaging pharmaceuticals for target-specific cancer detection. Details of preclinical and clinical evaluations of the potential 124I-labeled immunoPET imaging pharmaceuticals are described here.

scholarly journals Highly Sensitive Fluorescent Detection of Acetylcholine Based on the Enhanced Peroxidase-Like Activity of Histidine Coated Magnetic Nanoparticles

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1207
Author(s):  
Hong Jae Cheon ◽  
Quynh Huong Nguyen ◽  
Moon Il Kim
Keyword(s):  
Magnetic Nanoparticles ◽  
High Sensitivity ◽  
High Specificity ◽  
Choline Oxidase ◽  
Fluorescent Detection ◽  
One Pot ◽  
Site Structure ◽  
Specificity And Sensitivity ◽  
Highly Sensitive ◽  
Peroxidase Mimics

Inspired by the active site structure of natural horseradish peroxidase having iron as a pivotal element with coordinated histidine residues, we have developed histidine coated magnetic nanoparticles (His@MNPs) with relatively uniform and small sizes (less than 10 nm) through one-pot heat treatment. In comparison to pristine MNPs and other amino acid coated MNPs, His@MNPs exhibited a considerably enhanced peroxidase-imitating activity, approaching 10-fold higher in catalytic reactions. With the high activity, His@MNPs then were exploited to detect the important neurotransmitter acetylcholine. By coupling choline oxidase and acetylcholine esterase with His@MNPs as peroxidase mimics, target choline and acetylcholine were successfully detected via fluorescent mode with high specificity and sensitivity with the limits of detection down to 200 and 100 nM, respectively. The diagnostic capability of the method is demonstrated by analyzing acetylcholine in human blood serum. This study thus demonstrates the potential of utilizing His@MNPs as peroxidase-mimicking nanozymes for detecting important biological and clinical targets with high sensitivity and reliability.

scholarly journals The Use of BEREP4 Immunohistochemistry Staining for Detection of Basal Cell Carcinoma

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Anthony Paulo Sunjaya ◽  
Angela Felicia Sunjaya ◽  
Sukmawati Tansil Tan
Keyword(s):  
Basal Cell Carcinoma ◽  
Cell Carcinoma ◽  
Basal Cell ◽  
High Sensitivity ◽  
Common Type ◽  
Routine Examination ◽  
Cancer Society ◽  
Immunohistochemistry Staining ◽  
The World ◽  
Local Destruction

Basal Cell Carcinoma (BCC) is the most common type of malignant cancer found in the world today with a 3–10% increase in incidence each year. The American Cancer Society reported that 8 out of 10 patients with skin cancer are suffering from BCC with over 2 million new cases each year. BCC needs to be detected at the early stages to prevent local destruction causing disabilities to patients and increasing treatment costs. Furthermore, BCC patients who have undergone surgery are still at risk for recurrence, especially when the surgery performed fails to remove all the BCC cells, even when conventional histopathological testing after surgery has reported a surgically free margin. This review aims to evaluate studies on the use of BerEP4 immunohistochemistry staining on pathological sections of various types of BCC as well as its shortfalls. BerEP4 is a monoclonal antibody which detects specific epithelial-glycoprotein-adhesion-molecules (EpCAM) found on BCC cells. Various studies have shown that BerEP4 has a high sensitivity and specificity in detecting only BCC cells. The use of BerEP4 immunohistochemistry testing for the routine examination of cases of BCC is expected to be able to increase and improve early diagnosis as well as prevent recurrence after surgery.

scholarly journals Competition between Metals for Binding to Methanobactin Enables Expression of Soluble Methane Monooxygenase in the Presence of Copper

2014 ◽  
Vol 81 (3) ◽  
pp. 1024-1031 ◽  
Author(s):  
Bhagyalakshmi Kalidass ◽  
Muhammad Farhan Ul-Haque ◽  
Bipin S. Baral ◽  
Alan A. DiSpirito ◽  
Jeremy D. Semrau
Keyword(s):  
Methane Monooxygenase ◽  
High Specificity ◽  
Copper Uptake ◽  
Content Type ◽  
Soluble Methane Monooxygenase ◽  
Sds Page ◽  
Genes Encoding ◽  
Key Factor ◽  
Membrane Bound

ABSTRACTIt is well known that copper is a key factor regulating expression of the two forms of methane monooxygenase found in proteobacterial methanotrophs. Of these forms, the cytoplasmic, or soluble, methane monooxygenase (sMMO) is expressed only at low copper concentrations. The membrane-bound, or particulate, methane monooxygenase (pMMO) is constitutively expressed with respect to copper, and such expression increases with increasing copper. Recent findings have shown that copper uptake is mediated by a modified polypeptide, or chalkophore, termed methanobactin. Although methanobactin has high specificity for copper, it can bind other metals, e.g., gold. Here we show that inMethylosinus trichosporiumOB3b, sMMO is expressed and active in the presence of copper if gold is also simultaneously present. Such expression appears to be due to gold binding to methanobactin produced byM. trichosporiumOB3b, thereby limiting copper uptake. Such expression and activity, however, was significantly reduced if methanobactin preloaded with copper was also added. Further, quantitative reverse transcriptase PCR (RT-qPCR) of transcripts of genes encoding polypeptides of both forms of MMO and SDS-PAGE results indicate that both sMMO and pMMO can be expressed when copper and gold are present, as gold effectively competes with copper for binding to methanobactin. Such findings suggest that under certain geochemical conditions, both forms of MMO may be expressed and activein situ. Finally, these findings also suggest strategies whereby field sites can be manipulated to enhance sMMO expression, i.e., through the addition of a metal that can compete with copper for binding to methanobactin.

Cds nanocrystal enhanced TiO2photoelectrochemical aptasensor for sensitive detection of cytochrome c

2021 ◽  
Vol 11 (11) ◽  
pp. 1774-1780
Author(s):  
Shanji Fan ◽  
Hong Huang ◽  
Hong Chen ◽  
Jiachi Xu ◽  
Zecheng Hu ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Limit Of Detection ◽  
Specific Binding ◽  
High Sensitivity ◽  
High Specificity ◽  
Linear Range ◽  
Current Intensity ◽  
Sensitive Detection ◽  
Layer Adsorption ◽  
Ionic Layer

A CdS nanocrystal enhanced TiO2 nanotubes (CdS@TiO2 NATs) photoelectrode was prepared via successive ionic layer adsorption and reaction (SILAR) of CdS on the surface of TiO2 NATs. A HS-aptamer owing a specific binding toward cytochrome c was modified onto the CdS@TiO2 NATs, which resulting a decrease in the photoelectrical current intensity. Cytochrome c is therefore quantified based on the decrease in photoelectrical current. High specificity and high sensitivity were obtained with a linear range from 3 pM to 80 nM, and a limit of detection of 2.53 pM.

scholarly journals A 16S rDNA-based nested PCR protocol to detect Campylobacter gracilis in oral infections

2003 ◽  
Vol 17 (2) ◽  
pp. 142-146 ◽  
Author(s):  
José Freitas Siqueira Júnior ◽  
Isabela das Neves Rôças
Keyword(s):  
16S Rdna ◽  
High Sensitivity ◽  
High Specificity ◽  
Cross Reactivity ◽  
Nested Polymerase Chain Reaction ◽  
Oral Infections ◽  
Root Canals ◽  
Infected Root ◽  
Pcr Products ◽  
Species Specific

The aim of this study was to describe a 16S rDNA-based nested polymerase chain reaction (nPCR) assay to investigate the occurrence of Campylobacter gracilis in oral infections. Samples were collected from ten infected root canals, ten cases of acute periradicular abscesses and eight cases of adult marginal periodontitis. DNA extracted from the samples was initially amplified using universal 16S rDNA primers. A second round of amplification used the first PCR products to detect C. gracilis using oligonucleotide primers designed from species-specific 16S rDNA signature sequences. The nPCR assay used in this study showed a detection limit of 10 C. gracilis cells and no cross-reactivity was observed with nontarget bacteria. C. gracilis was detected in the three types of oral infections investigated - 4/10 infected root canals; 2/10 acute periradicular abscesses; and 1/8 subgingival specimens from adult periodontitis. The method proposed in this study showed both high sensitivity and high specificity to directly detect C. gracilis in samples from root canal infections, abscesses, and subgingival plaque. Our findings confirmed that C. gracilis may be a member of the microbiota associated with distinct oral infections, and its specific role in such diseases requires further clarification.

Design of Photoionization Detector Based on the Miniature Gas Chromatography

2013 ◽  
Vol 823 ◽  
pp. 291-295 ◽  
Author(s):  
Shou Chen Chai ◽  
Peng Yang ◽  
Cheng Jia Yang ◽  
Chun Li Cai ◽  
Na Yu
Keyword(s):  
Gas Chromatography ◽  
Detection Limit ◽  
Ionization Chamber ◽  
High Sensitivity ◽  
Fast Response ◽  
Low Detection Limit ◽  
Photoionization Detector ◽  
Key Factor ◽  
The Stability ◽  
Sensitivity Detection

In the space restricted airtight environment that people lives in, detecting harmful gas by miniature gas chromatography is the practical requirement at present, however, PIDs performance is key factor that restrict the application of miniature gas chromatography, the redesign of the detectors gas route in this paper aiming at improve detectors stability observably, and schemed out miniature PID with high sensitivity, low detection limit and fast response. The result of the experiment shows that the detection limit is 0.04ppm, the sensitivity is 101mv/ppm,the stability is 0.04×10-6/24h,meeting the project requirement. Keywords: photoionization detector; ionization chamber; sensitivity; detection limit;

scholarly journals Comparison between near miss criteria in a maternal intensive care unit

2018 ◽  
Vol 52 (0) ◽  
Author(s):  
Alana Santos Monte ◽  
Liana Mara Rocha Teles ◽  
Mônica Oliveira Batista Oriá ◽  
Francisco Herlânio Costa Carvalho ◽  
Helen Brown ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Maternal Death ◽  
High Sensitivity ◽  
High Specificity ◽  
Near Miss ◽  
World Health ◽  
Maternal Near Miss ◽  
Chi Square ◽  
Cross Sectional

ABSTRACT Objective: The aim of this study was to compare the incidence of different criteria of maternal near miss in women admitted to an obstetric intensive care unit and their sensitivity and specificity in identifying cases that have evolved to morbidity. Method: A cross-sectional analytical epidemiological study was conducted with women admitted to the intensive care unit of the Maternity School Assis Chateaubriand in Ceará, Brazil. The Chi-square test and odds ratio were used. Results: 560 records were analyzed. The incidence of maternal near miss ranged from 20.7 in the Waterstone criteria to 12.4 in the Geller criteria. The maternal near-miss mortality ratio varied from 4.6:1 to 7.1:1, showing better index in the Waterstone criteria, which encompasses a greater spectrum of severity. The Geller and Mantel criteria, however, presented high sensitivity and low specificity. Except for the Waterstone criteria, there was an association between the three other criteria and maternal death. Conclusion: The high specificity of Geller and Mantel criteria in identifying maternal near miss considering the World Health Organization criteria as a gold standard and a lack of association between the criteria of Waterstone with maternal death.

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