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https://www.readbyqxmd.com/read/28445636/disposable-autonomous-device-for-rapid-swab-to-result-diagnosis-of-influenza
#1
Shichu Huang, Koji Abe, Steven Bennett, Tinny Liang, Paula D Ladd, Lindsay Yokobe, Caitlin E Anderson, Kamal Shah, Josh Bishop, Mike Purfield, Peter C Kauffman, Sai Paul, AnneMarie E Welch, Bonnie Strelitz, Kristin Follmer, Kelsey Pullar, Luis Sanchez-Erebia, Emily Gerth-Guyette, Gonzalo J Domingo, Eileen Klein, Janet A Englund, Elain Fu, Paul Yager
A prototype of a self-contained, automated, disposable device for chemically-amplified protein-based detection of influenza virus from nasal swab specimens was developed and evaluated in a clinical setting. The device required only simple specimen manipulation without any dedicated instrumentation or specialized training by the operator for interpretation. The device was based on a sandwich immunoassay for influenza virus nucleoprotein; it used an enzyme-labeled antibody and a chromogenic substrate to provide an amplified visible signal, in a two-dimensional paper network format...
April 26, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28444620/environmental-pollution-with-antimicrobial-agents-from-bulk-drug-manufacturing-industries-in-hyderabad-south-india-is-associated-with-dissemination-of-extended-spectrum-beta-lactamase-and-carbapenemase-producing-pathogens
#2
Christoph Lübbert, Christian Baars, Anil Dayakar, Norman Lippmann, Arne C Rodloff, Martina Kinzig, Fritz Sörgel
PURPOSE: High antibiotic and antifungal concentrations in wastewater from anti-infective drug production may exert selection pressure for multidrug-resistant (MDR) pathogens. We investigated the environmental presence of active pharmaceutical ingredients and their association with MDR Gram-negative bacteria in Hyderabad, South India, a major production area for the global bulk drug market. METHODS: From Nov 19 to 28, 2016, water samples were collected from the direct environment of bulk drug manufacturing facilities, the vicinity of two sewage treatment plants, the Musi River, and habitats in Hyderabad and nearby villages...
April 26, 2017: Infection
https://www.readbyqxmd.com/read/28441767/inhibitory-effect-of-triterpenoids-from-panax-ginseng-on-coagulation-factor-x
#3
Lingxin Xiong, Zeng Qi, Bingzhen Zheng, Zhuo Li, Fang Wang, Jinping Liu, Pingya Li
Enzymes involved in the coagulation process have received great attention as potential targets for the development of oral anti-coagulants. Among these enzymes, coagulation factor Xa (FXa) has remained the center of attention in the last decade. In this study, 16 ginsenosides and two sapogenins were isolated, identified and quantified. To determine the inhibitory potential on FXa, the chromogenic substrates method was used. The assay suggested that compounds 5, 13 and 18 were mainly responsible for the anti-coagulant effect...
April 24, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28440032/discrepancies-between-the-one-stage-clotting-assay-and-the-chromogenic-assay-in-haemophilia-b
#4
K Kihlberg, K Strandberg, S Rosén, R Ljung, J Astermark
INTRODUCTION: Assay discrepancy in factor VIII activity between the one-stage and the chromogenic assays has been described in approximately one third of patients with non-severe haemophilia A. Whether assay discrepancy may also occur in patients with haemophilia B remains unknown. AIM: This study compared the results from the one-stage and the chromogenic assays in patients with haemophilia B. METHODS: Plasma samples from patients with haemophilia B attending the haemophilia centre in Malmö, Sweden, were collected after a wash-out period of more than 7 days and analysed with both assays...
April 24, 2017: Haemophilia: the Official Journal of the World Federation of Hemophilia
https://www.readbyqxmd.com/read/28438093/tyramide-signal-amplification-permits-immunohistochemical-analyses-of-androgen-receptors-in-the-rat-prefrontal-cortex
#5
Katelyn L Low, Chunqi Ma, Kiran K Soma
Research on neural androgen receptors (ARs) has traditionally focused on brain regions that regulate reproductive and aggressive behaviors, such as the hypothalamus and amygdala. Although many cells in the prefrontal cortex (PFC) also express ARs, the number of ARs per cell appears to be much lower, and thus, AR immunostaining is often hard to detect and quantify in the PFC. Here, we demonstrate that biotin tyramide signal amplification (TSA) dramatically increases AR immunoreactivity in the rat brain, including critical regions of the PFC such as the medial PFC (mPFC) and orbitofrontal cortex (OFC)...
May 2017: Journal of Histochemistry and Cytochemistry: Official Journal of the Histochemistry Society
https://www.readbyqxmd.com/read/28437103/ion-pair-oligomerization-of-chromogenic-triangulenium-cations-with-cyanostar-modified-anions-that-controls-emission-in-hierarchical-materials
#6
Bo Qiao, Brandon E Hirsch, Semin Lee, Maren Pink, Chun-Hsing Chen, Bo W Laursen, Amar H Flood
The hierarchical assembly of colored cationic molecules with receptor-modified counteranions can be used to control optical properties in materials. However, our knowledge of when the optical properties emerge in the hierarchical organization and the variety of cation-anion salts that are available to create these materials is limited. In this work, we extend the salts from small halides to large inorganic anions and determine how the structure coevolves with the emission properties using solution assemblies...
April 24, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28430959/expression-immunogenicity-and-variation-of-iron-regulated-surface-protein-a-from-bovine-isolates-of-staphylococcus-aureus
#7
N Misra, T F Wines, C L Knopp, M A McGuire, J K Tinker
Staphylococcus aureus iron-regulated surface protein A (IsdA) is a fibrinogen and fibronectin adhesin that also contributes to iron sequestration and resistance to innate immunity. IsdA is conserved in human isolates and has been investigated as a human vaccine candidate. Here we report the expression of isdA, the efficacy of anti-IsdA responses, and the existence of IsdA sequence variants from bovine Staphylococcus. Clinical staphylococci were obtained from U.S. dairy farms and assayed by PCR for the presence and expression of isdA...
April 19, 2017: FEMS Microbiology Letters
https://www.readbyqxmd.com/read/28429220/antithrombin-activity-of-erythrocyte-microvesicles
#8
G Ya Levin, E G Sukhareva
Coagulation and optical (based on chromogenic substrate) methods were employed to examine antithrombin activity of erythrocytes and erythrocyte-derived microvesicles isolated days 7, 14, 21, and 28 on erythrocyte storage. The erythrocyte-derived microvesicles decelerated fibrin clot formation from fibrinogen in the presence of exogenous thrombin both with and without heparin. Microvesicles reduced optical density of chromogenic substrate. These data suggest that erythrocyte-derived microvesicles display a prominent antithrombin activity, which significantly increases during erythrocyte storage...
April 21, 2017: Bulletin of Experimental Biology and Medicine
https://www.readbyqxmd.com/read/28428193/pd-l1-expression-in-melanoma-a-quantitative-immunohistochemical-antibody-comparison
#9
Joel C Sunshine, Peter Nguyen, Genevieve Kaunitz, Tricia Cottrell, Sneha Berry, Jessica Esandrio, Haiying Xu, Aleksandra Ogurtsova, Karen R Bleich, Toby C Cornish, Evan J Lipson, Robert A Anders, Janis Taube
PD-L1 expression in the pre-treatment tumor microenvironment enriches for response to anti-PD-1/PD-L1 therapies. The purpose of this study was to quantitatively compare the performance of five monoclonal anti-PD-L1 antibodies used in recent landmark publications.  <br /><br />Experimental Design: PD-L1 immunohistochemistry (IHC) was performed on thirty-four formalin-fixed paraffin-embedded archival melanoma samples using the 5H1, SP142, 28-8, 22C3 and SP263 clones.  The percentage of total cells (including melanocytes and immune cells) demonstrating cell surface PD-L1 staining, as well as intensity measurements/H-scores, were assessed for each melanoma specimen using a computer-assisted platform...
April 20, 2017: Clinical Cancer Research: An Official Journal of the American Association for Cancer Research
https://www.readbyqxmd.com/read/28423089/phenotypic-and-genotypic-detection-of-candida-albicans-and-candida-dubliniensis-strains-isolated-from-oral-mucosa-of-aids-pediatric-patients
#10
Harisson Oliveira Livério, Luciana da Silva Ruiz, Roseli Santos de Freitas, Angela Nishikaku, Ana Clara de Souza, Claudete Rodrigues Paula, Carina Domaneschi
The aim of this study was to assess a collection of yeasts to verify the presence of Candida dubliniensis among strains isolated from the oral mucosa of AIDS pediatric patients which were initially characterized as Candida albicans by the traditional phenotypic method, as well as to evaluate the main phenotypic methods used in the discrimination between the two species and confirm the identification through genotypic techniques, i.e., DNA sequencing. Twenty-nine samples of C. albicans isolated from this population and kept in a fungi collection were evaluated and re-characterized...
April 13, 2017: Revista do Instituto de Medicina Tropical de São Paulo
https://www.readbyqxmd.com/read/28419503/comparison-of-the-quantitative-dry-culture-methods-with-both-conventional-media-and-most-probable-number-method-for-the-enumeration-of-coliforms-and-escherichia-coli-coliforms-in-food
#11
Hajime Teramura, Kojiro Sota, Mihoko Iwasaki, Hirokazu Ogihara
Sanita-kun(™) CC (coliform count) and EC (Escherichia coli/coliform count), sheet quantitative culture systems which can avoid chromogenic interference by lactase in food, were evaluated in comparison with conventional methods for these bacteria. Based on the results of inclusivity and exclusivity studies using 77 microorganisms, sensitivity and specificity of both Sanita-kun(™) met the criteria for ISO 16140. Both media were compared with deoxycholate agar, violet red bile agar, Merck Chromocult(™) coliform agar (CCA), 3M Petrifilm(™) CC and EC (PEC), and 3-tube MPN, as reference methods, in 100 naturally contaminated food samples...
April 17, 2017: Letters in Applied Microbiology
https://www.readbyqxmd.com/read/28418715/evaluation-of-selective-enrichment-and-chromogenic-media-for-salmonella-detection-in-raw-shell-egg-contents-with-a-low-microbial-load
#12
Soo-Kyoung Lee, Kwang-Young Song, Jung-Whan Chon, Dong-Hyeon Kim, Kun-Ho Seo
The current study was conducted to evaluate the ability to recover Salmonella from shell egg contents by culture methods. A total of 4,000 eggs were obtained from a grading and packing center located in the Gyeonggi Province of South Korea, and 200 samples were created by pooling 20 broken eggs. The pooled samples were held at room temperature for 4 d before a 25-mL aliquot of each pool was added to 225 mL of modified trypticase soy broth (mTSB) and incubated at 35°C for 24 ± 2 h. A loopful of the culture was streaked onto chromogenic Druggan-Forsythe-Iversen (DFI) agar and incubated at 36 ± 1°C for 18-24 h...
April 18, 2017: Foodborne Pathogens and Disease
https://www.readbyqxmd.com/read/28411223/modified-bacteriophage-s16-long-tail-fiber-proteins-for-rapid-and-specific-immobilization-and-detection-of-salmonella-cells
#13
Jenna M Denyes, Matthew Dunne, Stanislava Steiner, Maximilian Mittelviefhaus, Agnes Weiss, Herbert Schmidt, Jochen Klumpp, Martin J Loessner
Bacteriophage-based assays and biosensors rival traditional antibody-based immunoassays for detection of low-level Salmonella contaminations. In this study, we harnessed the binding specificity of the long tail fiber (LTF) from bacteriophage S16 as an affinity molecule for immobilization, enrichment, and detection of Salmonella We demonstrate that paramagnetic beads (MBs) coated with recombinant gp37-gp38 LTF complexes (LTF-MBs) are highly effective tools for rapid affinity magnetic separation and enrichment of Salmonella Within 45 minutes, the LTF-MBs consistently captured over 95% of Salmonella Typhimurium cells from suspensions containing 10-10(5) CFU...
April 14, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28406575/monitoring-once-weekly-recombinant-factor-ix-prophylaxis-in-hemophilia-b-with-thrombin-generation-assay-and-factor-ix-activity
#14
V Nummi, A Jouppila, R Lassila
INTRODUCTION: Prophylaxis is the recommended treatment mode for severe hemophilia B. However, no single treatment regimen fits for all patients. Once-weekly prophylaxis with high-dose recombinant factor IX (rFIX) is efficacious, nevertheless, laboratory outcomes following 72 h after administration are lacking. METHODS: In a prospective open-label noncomparative study, 10 severe/moderate (FIX ≤2 IU/dL) adult patients received rFIX dose (60-100 IU/kg) after >72 h washout on two occasions, separated by 7 days...
April 13, 2017: International Journal of Laboratory Hematology
https://www.readbyqxmd.com/read/28405804/cytoprotective-drug-tissue-plasminogen-activator-protease-interaction-assays-screening-of-two-novel-cytoprotective-chromones
#15
Paul A Lapchak, Jacqueline M Lara, Paul D Boitano
Tissue plasminogen activator (tPA) is currently used in combination with endovascular procedures to enhance recanalization and cerebral reperfusion and is also currently administered as standard-of-care thrombolytic therapy to patients within 3-4.5 h of an ischemic stroke. Since tPA is not neuroprotective or cytoprotective, adjuvant therapy with a neuroprotective or an optimized cytoprotective compound is required to provide the best care to stroke victims to maximally promote clinical recovery. In this article, we describe the use of a sensitive standardized protease assay with CH3SO2-D-hexahydrotyrosine-Gly-Arg-p-nitroanilide•AcOH, a chromogenic protease substrate that is cleaved to 4-nitroaniline (p-nitroaniline) and measured spectrophotometrically at 405 nm (OD405 nm), and how the assay can be used as an effective screening assay to study drug-tPA interactions...
April 12, 2017: Translational Stroke Research
https://www.readbyqxmd.com/read/28403147/cryptosporidium-spp-and-giardia-spp-in-feces-and-water-and-the-associated-exposure-factors-on-dairy-farms
#16
Roberta Dos Santos Toledo, Felippe Danyel Cardoso Martins, Fernanda Pinto Ferreira, Jonatas Campos de Almeida, Liza Ogawa, Hannah Lia Ettiene Peruch Lemos Dos Santos, Maíra Moreira Dos Santos, Filipe Aguera Pinheiro, Italmar Teodorico Navarro, João Luis Garcia, Roberta Lemos Freire
The aims of this study were to verify the prevalence of Cryptosporidium spp. and Giardia spp. in animal feces and drinking water on dairy farms and to identify a possible relation between the exposure factors and the presence of these parasites. Fecal samples from cattle and humans and water samples were collected on dairy farms in Paraná, Brazil. Analysis of (oo)cysts in the feces was performed by the modified Ziehl-Neelsen staining and centrifugal flotation in zinc sulfate. Test-positive samples were subjected to nested PCR amplification of the 18SSU ribosomal RNA gene for identification of Cryptosporidium and Giardia and of the gp60 gene for subtyping of Cryptosporidium...
2017: PloS One
https://www.readbyqxmd.com/read/28389152/detection-of-l-alanylaminopeptidase-activity-in-microorganisms-using-chromogenic-self-immolative-enzyme-substrates
#17
Marie Cellier, Arthur L James, Sylvain Orenga, John D Perry, Ari K Rasul, Stephen P Stanforth
Three potential chromogenic enzymatic probes, each possessing a self-immolative spacer unit, were synthesised for the purpose of detecting l-alanylaminopeptidase activity in microorganisms. An Alizarin-based probe was the most effective, allowing several species to generate strongly coloured colonies in the presence of metal ions.
March 28, 2017: Bioorganic & Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/28387704/quantitative-detection-of-nadh-using-a-novel-enzyme-assisted-method-based-on-surface-enhanced-raman-scattering
#18
Haiyan Teng, Mingyang Lv, Luo Liu, Xin Zhang, Yongmei Zhao, Zhenglong Wu, Haijun Xu
An enzymatic method for quantitative detection of the reduced form of nicotinamide-adenine dinucleotide (NADH) using surface-enhanced Raman scattering was developed. Under the action of NADH oxidase and horseradish peroxidase, NADH can generate hydrogen peroxide (H₂O₂) in a 1:1 molar ratio, and the H₂O₂ can oxidize a chromogen into pigment with a 1:1 molar ratio. Therefore, the concentration of NADH can be determined by detecting the generated pigment. In our experiments, eight chromogens were studied, and o-tolidine (OT) was selected because of the unique Raman peaks displayed by its corresponding pigment...
April 7, 2017: Sensors
https://www.readbyqxmd.com/read/28384443/effect-of-platelet-derived-%C3%AE-thromboglobulins-on-coagulation
#19
Karl Egan, Johanna P van Geffen, Hui Ma, Barry Kevane, Aine Lennon, Seamus Allen, Elaine Neary, Martin Parsons, Patricia Maguire, Kieran Wynne, Richard O' Kennedy, Johan W M Heemskerk, Fionnuala Ní Áinle
BACKGROUND: β-thromboglobulins are derived from the cleavage of the CXC chemokine platelet basic protein and are released in high concentrations by activated platelets. Platelet-derived β-thromboglobulins (βTG) share 70% homology with platelet factor 4 (PF4), another CXC chemokine released by activated platelets. PF4 modulates coagulation by inhibiting heparin-antithrombin interactions, promoting protein C activation, and attenuating the activity of activated protein C. In contrast, the effect of βTG on coagulation is unknown...
March 30, 2017: Thrombosis Research
https://www.readbyqxmd.com/read/28382824/modulation-of-the-singlet-oxygen-generation-from-the-double-strand-dna-sybr-green-i-complex-mediated-by-t-melamine-t-mismatch-for-visual-detection-of-melamine
#20
Hao Hu, Jinyi Zhang, Yu Ding, Xinfeng Zhang, Kailai Xu, Xiandeng Hou, Peng Wu
Singlet oxygen ((1)O2), generated via photosensitization, has been proved to oxidize chromogenic substrates with neither H2O2 oxidation nor enzyme (horseradish peroxidase, HRP) catalysis. Of the various methods for modulation of the (1)O2 generation, DNA-controlled photosensitization received great attention. Therefore, integration of the formation/deformation DNA structures with DNA-controlled photosensitization will be extremely appealing in visual biosensor developments. Here, the stable melamine-thymine complex was explored in combination with DNA-controlled photosensitization for visual detection of melamine...
April 12, 2017: Analytical Chemistry
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