332 results on '"Benzophenoneidum"'
Search Results
52. Evaluation of Auramine O staining and conventional PCR for leprosy diagnosis: A comparative cross-sectional study from Ethiopia
- Author
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Kassu Desta, Tsegaye Hailu, Munir H. Idriss, Selfu Girma, Yohannes Tsegaye, Abraham Aseffa, Stewart T. Cole, Philippe Busso, Charlotte Avanzi, Shimelis D. Nigusse, and Kidist Bobosha
- Subjects
Male ,Polymerase Chain Reaction ,Gastroenterology ,030207 dermatology & venereal diseases ,chemistry.chemical_compound ,0302 clinical medicine ,Coloring Agents ,slit-skin smear ,Eosin ,Auramine O ,lcsh:Public aspects of medicine ,Middle Aged ,Infectious Diseases ,Real-time polymerase chain reaction ,Benzophenoneidum ,Ziehl–Neelsen stain ,Female ,Adult ,medicine.medical_specialty ,lcsh:Arctic medicine. Tropical medicine ,Adolescent ,lcsh:RC955-962 ,030231 tropical medicine ,polymerase-chain-reaction ,challenges ,Haematoxylin ,Sensitivity and Specificity ,Young Adult ,mycobacterium-leprae ,03 medical and health sciences ,Leprosy ,Internal medicine ,medicine ,Humans ,relevance ,Aged ,Bacteriological Techniques ,disease ,Staining and Labeling ,Diagnostic Tests, Routine ,bacilli ,business.industry ,Public Health, Environmental and Occupational Health ,biopsies ,lcsh:RA1-1270 ,Gold standard (test) ,DNA extraction ,Staining ,Cross-Sectional Studies ,chemistry ,Ethiopia ,business - Abstract
Background, Diagnosis of leprosy mainly relies on clinical examination due to the inconsistent sensitivity and poor reproducibility of the current laboratory tests. Utilisation of alternative methods to the standard Ziehl Neelsen (ZN), Fite-Faraco (FF) and Haematoxylin and Eosin (H&E) staining procedures may eventually improve leprosy diagnosis., Methodology/Principal findings, In this comparative study, the performance of the fluorescent Auramine O (AO) staining and polymerase chain reaction (PCR) was assessed with different skin samples using a combination of ZN, FF and H&E staining as the gold standard. AO, ZN, FF, H&E and PCR tests were performed on slit skin smears (SSS) and/or punch biopsies collected from 141 clinically confirmed leprosy cases and 28 non-leprosy skin samples. DNA was extracted from punch biopsies using two different methods with or without mechanical lysis., Sensitivities were 87.6%, 59.3% and 77% for H&E, ZN and FF, respectively, whereas it reached 65.5% and 77.9% for AO in SSS and tissue sections and 91.1% for PCR in tissue samples. Morover, samples with low bacillary index, sensitivity of AO staining (61.8%) was similar to FF (60%, p>0.05) and lower than PCR (86.6%, p, Conclusions/Significance, Our results showed that for diagnostic purposes, analysis of skin section is more sensitive than SSS, especially for samples with low bacillary load. AO staining on SSS and tissue sections was not significantly better than other routine diagnostic tests but considerably more user friendly. The sensitivity of PCR was higher than current standard methods and increased when combined with more efficient DNA extraction using mechanical and chemical lysis. Therefore, we recommend AO staining for the diagnosis of leprosy in lower health facilities such as health centres and district hospitals and PCR diagnosis at referral level and research centres.
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- 2018
53. Monoolein cubic phases containing cinnamic acid, poly(ethyleneimine) and gold nanoparticle and their UV- and NIR-responsive release property
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Jin-Chul Kim and Danbi Park
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Infrared Rays ,Ultraviolet Rays ,Pharmaceutical Science ,Nanoparticle ,Metal Nanoparticles ,macromolecular substances ,02 engineering and technology ,030226 pharmacology & pharmacy ,Cinnamic acid ,Glycerides ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Phase (matter) ,Polyethyleneimine ,Irradiation ,Fluorescent Dyes ,Auramine O ,Chemistry ,technology, industry, and agriculture ,Ethyleneimine ,Dextrans ,021001 nanoscience & nanotechnology ,Drug Liberation ,Benzophenoneidum ,Cinnamates ,Gold ,0210 nano-technology ,Isomerization ,Fluorescein-5-isothiocyanate ,Conjugate ,Nuclear chemistry - Abstract
UV and NIR-responsive monoolein cubic phase was prepared by including poly(ethyleneimine) (PEI)/cinnamic acid (CA) conjugate and gold nanoparticle (GNP) within its structure. UV irradiation elevated significantly the release % of Auramine O loaded in cubic phase containing PEI/CA, possibly because of the trans-to-cis isomerization of CA. NIR irradiation also increased significantly the release % of FITC-dextran loaded in cubic phase containing PEI/CA. The release % of the dye loaded in cubic phase containing PEI/CA and GNP was elevated more markedly by NIR irradiation, possibly due to the phase transition of cubic phase and the disassembling of PEI/CA assembly.
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- 2017
54. Sputum induction is a safe procedure to use in prisoners and MGIT is the best culture method to diagnose tuberculosis in prisons: a cohort study
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Zulma Vanessa Rueda, Diana Marín, María Patricia Arbeláez, Lucelly López, and Lázaro Vélez
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Male ,Microbiology (medical) ,medicine.medical_specialty ,Time Factors ,Tuberculosis ,Concordance ,Culture techniques ,Diagnostic Techniques, Respiratory System ,Induced sputum ,behavioral disciplines and activities ,lcsh:Infectious and parasitic diseases ,Cohort Studies ,Pulmonary tuberculosis ,Internal medicine ,Diagnosis ,mental disorders ,medicine ,Humans ,lcsh:RC109-216 ,Mycobacteria growth indicator tube ,Prospective Studies ,Coloring Agents ,Tuberculosis, Pulmonary ,Bacteriological Techniques ,business.industry ,Prisoners ,Sputum ,virus diseases ,Mycobacterium tuberculosis ,social sciences ,General Medicine ,medicine.disease ,Confidence interval ,Culture Media ,Spontaneous sputum ,3. Good health ,Surgery ,Agar ,Infectious Diseases ,Benzophenoneidum ,Prisons ,population characteristics ,Female ,medicine.symptom ,business ,Cohort study - Abstract
Summary Objectives To evaluate the concordance and safety of induced sputum (IS) and spontaneous sputum (SS), and estimate concordance and time to detection of M. tuberculosis between Lowenstein–Jensen (LJ), thin-layer agar (TLA), and the Mycobacteria Growth Indicator Tube system (MGIT). Methods This was a cohort study. Prisoners with pulmonary tuberculosis (PTB) were followed for 2 years. At baseline and every follow-up visit, three sputum samples were taken on consecutive days (one IS and two SS) and adverse events occurring before, during, and 30min after IS were registered. All sputum samples were stained with auramine and cultured in LJ, TLA (to test resistance), and MGIT. Results Five hundred eighty-six IS and 532 SS were performed on 64 PTB patients. Breathlessness (1.6%), cough (1.2%), hemoptysis (0.3%), and cyanosis (0.2%) were the only complications. Concordance between IS and SS was 0.78 (95% confidence interval 0.69–0.87); 11 positive cultures from IS samples were negative in SS, and 11 positive cultures from SS samples were negative in IS. One hundred seventy-eight cultures were positive by any technique: MGIT 95%, LJ 73%, and TLA 57%. Time to detection of M. tuberculosis in LJ, TLA, and MGIT was 31, 18, and 11 days, respectively. Conclusions The IS procedure is safe in prisons. The MGIT system is better and faster than LJ and TLA in the diagnosis of M. tuberculosis .
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- 2015
55. A label-free fluorescent molecular switch for a DNA hybridization assay utilizing a G-quadruplex-selective auramine O
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Peng Qu, Fenghua Geng, Maotian Xu, Xinhe Lai, Huiying Xu, Yongxiang Wang, Baohong Liu, and Yintang Zhang
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Molecular switch ,Molecular Structure ,Auramine O ,Metals and Alloys ,Nucleic Acid Hybridization ,DNA ,General Chemistry ,G-quadruplex ,Signal ,Fluorescence ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,G-Quadruplexes ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Benzophenoneidum ,Materials Chemistry ,Ceramics and Composites ,Humans ,A-DNA ,Signal transduction ,Fluorescent Dyes - Abstract
A sensitive and selective assay of DNA is developed by utilizing a signal transduction strategy with the rational redesign of the hairpin structured G-quadruplex molecular switch (G4-MS) assembled using auramine O (AO). By monitoring the changes of the fluorescent signal, we could identify and further quantitatively determine the target DNA in the samples.
- Published
- 2015
56. Auramine-o (Synthetic Yellow Cow Dung Powder) Poisoning: Rare but Fatal
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Shubhangi, Dhadke, Vitthal, Dhadke, and Abhijit, Giram
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Adult ,Male ,Young Adult ,Adolescent ,Benzophenoneidum ,Humans ,India ,Female ,Prospective Studies ,Powders ,Disinfectants - Abstract
Cow dung known since long ago for its germicidal properties, used by Indian villagers to clean the house premises. As cow dung is not available easily, nowadays people have started using synthetic yellow coloured powder (Auramine-o) available easily in grocery shops locally known as "Morechap powder" in districts of Maharashtra. As the poisoning is rare, very few literatures are available mentioning the detailed mechanism of action, clinical presentation and complications.To study the clinical features, treatment and outcomes of synthetic yellow cow dung powder poisoning.25 patients presenting with confirmed H/O consumption of (Auramine-o) synthetic yellow cow dung powder poisoning were studied. Patient's routine investigations BSL, RFT, LFT were done. CT brain was done whenever indicated.Synthetic yellow cow dung powder poisoning was common in young age group and females. Vomiting, respiratory depression were common symptoms. Synthetic yellow cow dung powder poisoning was needed only symptomatic treatment. It was very rare and mortality is low when treated promptly.
- Published
- 2017
57. Fixed-bed column performances of azure-II and auramine-O adsorption by Pinus eldarica stalks activated carbon and its composite with zno nanoparticles: Optimization by response surface methodology based on central composite design
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Mehrorang Ghaedi, Maryam Jafari, Arash Asfaram, Mahmood Reza Rahimi, and Hamedreza Javadian
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Materials science ,Central composite design ,Analytical chemistry ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Azure Stains ,Water Purification ,Biomaterials ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Adsorption ,Mass transfer ,medicine ,Response surface methodology ,Aqueous solution ,Chromatography ,Auramine O ,Hydrogen-Ion Concentration ,021001 nanoscience & nanotechnology ,Pinus ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Volumetric flow rate ,chemistry ,Benzophenoneidum ,Charcoal ,Nanoparticles ,Zinc Oxide ,0210 nano-technology ,Water Pollutants, Chemical ,Activated carbon ,medicine.drug - Abstract
A continuous adsorption was used for removal of azure II (AZ II) and auramine O (AO) from aqueous solutions using Pinus eldarica stalks activated carbon (PES-AC) from aqueous solutions. The effects of initial dye concentration, flow rate, bed height and contact time on removal percentage of AO and AZ II were evaluated and optimized by central composite design (CCD) at optimum pH = 7.0. ZnO nanoparticles loaded on activated carbon were also used to remove AO and AZ II at pH = 7.0 and other optimum conditions. The breakthrough curves were obtained at different flow rates, initial dye concentrations and bed heights and the experimental data were fitted by Thomas, Adams–Bohart and Yoon–Nelson models. The main parameters of fixed-bed column including its adsorption capacity at breakthrough point (q b ), adsorption capacity at saturation point (q s ), mass transfer zone (MTZ), total removal percentage (R%), and empty bed contact time (EBCT) were calculated. The removal percentages calculated for AZ II and AO II were in the range of 51.6–61.1% and 40.6–61.6%, respectively. Bed adsorption capacity (N 0 ) and critical bed depth (Z 0 ) were obtained by BDST model.
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- 2017
58. Auramine-Phenol vs. Modified Kinyoun’s Acid-Fast Stains for Detection of Coccidia Parasites
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Maha R. Gaafar and Iman F. Abou El-Naga
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Adult ,Male ,Pathology ,medicine.medical_specialty ,Adolescent ,Clinical Biochemistry ,Auramine phenol ,Sensitivity and Specificity ,Stain ,Cyclospora cayetanensis ,Microbiology ,Feces ,Young Adult ,Coccidia ,Phenols ,parasitic diseases ,medicine ,Humans ,Child ,Coloring Agents ,biology ,Biochemistry (medical) ,Middle Aged ,biology.organism_classification ,Staining ,Cryptosporidium parvum ,Benzophenoneidum ,Child, Preschool ,Acid-fast ,Female - Abstract
Objective Auramine-phenol stain was compared with Kinyoun’s acid-fast stain to detect coccidia parasites in fecal samples from immunocompromised patients. The comparison was based on the number of detected cases, sensitivity, specificity, time required for the procedure, ease of use, interpretation, and cost. Methods A total of 112 fecal specimens were examined by conventional methods: Direct wet saline smear, iodine smear, and formol ether sedimentation technique. Duplicate smears of the fecal concentrates were stained by both procedures. Results Kinyoun’s and auramine-phenol stains detected 22 and 24 positive coccidia specimens respectively. The control group (27 immunocompetent relatives) showed a high incidence of Giardia lamblia infection. Kinyoun smears were difficult to interpret, while auramine smears were extremely easy to read, thus requiring less time. Artifacts were readily recognizable. The cost of auramine-phenol reagents was much higher than Kinyoun’s acid-fast stain. Conclusion Although the overall ranking of both staining techniques was high, the auramine-phenol stain was a more desirable test despite its higher cost. * C. parvum : Cryptosporidium parvum C. cayetanensis : Cyclospora cayetanensis AIDS : acquired immunodeficiency syndrome
- Published
- 2014
59. Auramine dyes induce toxic effects to aquatic organisms from different trophic levels: an application of predicted non-effect concentration (PNEC).
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de Jesus Azevedo CC, de Oliveira R, Suares-Rocha P, Sousa-Moura D, Li AT, Grisolia CK, de Aragão Umbuzeiro G, and Montagner CC
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- Animals, Benzophenoneidum, Coloring Agents, Daphnia, Reproducibility of Results, Aquatic Organisms, Water Pollutants, Chemical toxicity
- Abstract
The dyes Auramine and Auramine O are used in several industrial products, despite the scarce information regarding their ecotoxicity. The aim of the present study was to assess the acute and chronic toxicity of both dyes to aquatic organisms from different trophic levels (Raphidocelis subcapitata, Daphnia similis, Hydra attenuata, and Danio rerio) and calculate their predicted non-effect concentrations (PNEC). Auramine and Auramine O induced toxicity to all selected test organisms with L(E)C50 values ranging from 300 to 4800 ug/L. Both dyes induced inhibition in the growth rate of exposed algae, negatively affecting the reproduction of D. similis and induced deformities in H. attenuata (clubbed tentacles and shortened tentacles) and D. rerio (edemas, tail malformation and delay in yolk sac absorption). PNEC values of 0.92 μg/L and 4.0 μg/L were obtained for Auramine and Auramine O, respectively, based on results of the most sensitive test system (algae). Test results were analyzed using the Criteria of Reporting and Evaluating Ecotoxicity Data (CRED), confirming their reliability and relevance. Thus, PNEC values can be used in future risk assessments of those substances in freshwater systems.
- Published
- 2021
- Full Text
- View/download PDF
60. Blinded rechecking of acid-fast bacilli smears by light-emitting diode microscopy
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Vanaja Kumar, Rajesh Radhakrishnan, Nagamiah Selvakumar, S. Prabuseenivasan, A. Thomas, S. Balaji, and U. Sankar
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Quality Control ,Pulmonary and Respiratory Medicine ,Pathology ,medicine.medical_specialty ,Time Factors ,Auramine phenol ,Predictive Value of Tests ,Microscopy ,Humans ,Medicine ,False Positive Reactions ,Coloring Agents ,False Negative Reactions ,Tuberculosis, Pulmonary ,Observer Variation ,Staining and Labeling ,business.industry ,Sputum ,Reproducibility of Results ,Mycobacterium tuberculosis ,Infectious Diseases ,Microscopy, Fluorescence ,Benzophenoneidum ,Acid-fast ,Large study ,medicine.symptom ,business ,Nuclear medicine - Abstract
BACKGROUND: Blinded rechecking of auramine-stained acid-fast bacilli (AFB) sputum smears using fluorescence microscopy (FM), especially FM using light-emitting diode (LED), is not well understood. OBJECTIVE: To examine the rechecking of auramine-stained sputum smears without restaining within a month using LED FM. METHODS: A total of 4799 centrifuged smears of sputum samples were stained by the auramine phenol method and examined using LED FM; 564 systematically selected smears were subjected to blinded rechecking without restaining by controllers. The initial results of the readers were compared to those of the controllers. Discrepancies were resolved by a referee. The quality of LED FM was assessed by the referee using the culture result as gold standard. RESULTS: Among the rechecked smears, one high false-negative error was made by a reader, while one high false-positive error and 19 high false-negative errors were made by the controllers. The errors were resolved by culture. Smear results for 18 slides were not available due to AFB fading. CONCLUSION: AFB colour fading using LED FM, which affected the accurate evaluation of blinded rechecking of AFB smears without restaining within a month, is confirmed in this large study.
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- 2013
61. No added value of performing Ziehl-Neelsen on auramine-positive samples for tuberculosis diagnostics
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M Straetemans, M Scholing, A L den Hertog, S Daher, Richard M. Anthony, and KIT: Biomedical Research
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Adult ,Male ,Pulmonary and Respiratory Medicine ,Veterinary medicine ,Tuberculosis ,Adolescent ,Databases, Factual ,Mycobacterium Infections, Nontuberculous ,World health ,Young Adult ,Health services ,Tuberculosis diagnosis ,Tuberculosis diagnostics ,Humans ,Medicine ,Diagnostic data ,Child ,Coloring Agents ,Respiratory samples ,Aged ,Netherlands ,Retrospective Studies ,Aged, 80 and over ,Staining and Labeling ,business.industry ,Sputum ,Nontuberculous Mycobacteria ,Mycobacterium tuberculosis ,Middle Aged ,medicine.disease ,Cross-Sectional Studies ,Infectious Diseases ,Microscopy, Fluorescence ,Benzophenoneidum ,Child, Preschool ,Practice Guidelines as Topic ,Ziehl–Neelsen stain ,Female ,business - Abstract
Setting Regional Laboratory for Tuberculosis, Amsterdam, The Netherlands. Background There is a push to switch from Ziehl-Neelsen (ZN) to auramine microscopy. Despite World Health Organization guidelines that one staining method is sufficient, in some countries national guidelines prescribe that auramine-positive samples should be confirmed by ZN. Objective To investigate the added value of confirming auramine-positive samples using ZN. Design Using diagnostic data from 10 276 respiratory samples collected from 5525 patients tested for tuberculosis (TB) at the Municipal Health Service of Amsterdam between May 2006 and October 2011, we determined the diagnostic accuracy of auramine alone and of confirmation of auramine-positive samples using ZN. Results Of 141 M. tuberculosis complex-positive samples detected using auramine on which ZN was performed, 32 (22.7%) were ZN-negative. A similar percentage (6/25, 24.0%) of negatives was found for samples containing non-tuberculous mycobacteria (NTM) species, thus making it impossible to distinguish between TB and NTM on the basis of ZN results. Conclusions A positive auramine result followed by a negative ZN result could not be used to exclude TB or to indicate the presence of NTM species. Confirming auramine-positive samples using ZN in this setting thus provided no clinically informative information and was a waste of resources.
- Published
- 2013
62. Sensitivity of Fite-Faraco versus auramine-rhodamine in mycobacterial infection.
- Author
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Snyder AN, O'Connor H, Plante JG, Smith LJ, and Elston DM
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- Bacteriological Techniques methods, Drug Combinations, Female, Humans, Male, Retrospective Studies, Sensitivity and Specificity, Anti-Infective Agents, Benzophenoneidum, Coloring Agents, Fluorescent Dyes, Mycobacterium isolation & purification, Mycobacterium Infections microbiology, Rhodamines
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- 2020
- Full Text
- View/download PDF
63. Auramine-O as a Fluorescence Marker for the Detection of Amyloid Fibrils
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Dan Huppert and Nadav Amdursky
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Amyloid ,Auramine O ,Stereochemistry ,macromolecular substances ,Amyloid fibril ,Fluorescence ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Microscopy, Fluorescence ,chemistry ,Benzophenoneidum ,mental disorders ,Materials Chemistry ,Biophysics ,Spectrophotometry, Ultraviolet ,Physical and Theoretical Chemistry ,Fluorescent Dyes - Abstract
There is an indispensable need for a fluorescence marker for the detection of amyloid fibrils, where, at present, the most used marker is thioflavin-T (ThT). Here, we present the use of auramine-O (AuO) as a possible alternative to ThT. As with ThT, the increase in the emission of AuO upon binding to amyloid fibrils is the result of inhibition of the free rotation of the two dimethylamino arms of the molecule. This inhibition prevents the excited-state electronic wave function from moving from the emissive locally excited state to the dark charge-transfer state. We further show that not only AuO is comparable to ThT as a fluorescent marker for amyloid fibrils but also it has a unique spectroscopic signature. AuO has distinct two modes that are characterized by a large shift in the absorption and emission peak positions between its unbound and bound states (before and after the fibrils formation, respectively). In this context, we show that, whereas the emission band position is red-shifting, the absorption peak shifts to the blue and the spectrum exhibits an isosbestic point. The large shifts in emission and absorption peak positions can be explained by the photoacid activity of AuO exhibiting an excited-state proton-transfer process.
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- 2012
64. Evaluation of an Ultrafast Molecular Rotor, Auramine O, as a Fluorescent Amyloid Marker
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Niyati H. Mudliar, Aafrin M. Pettiwala, Prabhat K. Singh, and Biswajit Sadhu
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Circular dichroism ,Static Electricity ,macromolecular substances ,02 engineering and technology ,Plasma protein binding ,010402 general chemistry ,Fibril ,01 natural sciences ,chemistry.chemical_compound ,Protein structure ,Static electricity ,Materials Chemistry ,Animals ,Humans ,Insulin ,Benzothiazoles ,Physical and Theoretical Chemistry ,Bovine serum albumin ,Binding Sites ,Auramine O ,biology ,Circular Dichroism ,Temperature ,Serum Albumin, Bovine ,021001 nanoscience & nanotechnology ,Fluorescence ,0104 chemical sciences ,Surfaces, Coatings and Films ,Protein Structure, Tertiary ,Molecular Docking Simulation ,Crystallography ,Thiazoles ,chemistry ,Benzophenoneidum ,biology.protein ,Thermodynamics ,Cattle ,0210 nano-technology ,Hydrophobic and Hydrophilic Interactions ,Protein Binding - Abstract
Recently, Auramine O (AuO) has been projected as a fluorescent fibril sensor, and it has been claimed that AuO has an advantage over the most extensively utilized fibril marker, Thioflavin-T (ThT), owing to the presence of an additional large red-shifted emission band for AuO, which was observed exclusively for AuO in the presence of fibrillar media and not in protein or buffer media. As fibrils are very rich in β-sheet structure, a fibril sensor should be more specific toward the β-sheet structure so as to produce a large contrast between the fibril form and native protein form, for efficient detection and in vitro mechanistic studies of fibrillation. However, in this report, we show that AuO interacts significantly with the native form of bovine serum albumin (BSA), which is an all-α-helical protein and lacks the β-sheet structure, which are the hallmarks of a fibrillar structure. This strong interaction of AuO with the native form of BSA leads to a large emission enhancement of AuO for the native protein itself, and leads to a low contrast between the BSA protein and its fibrils. More importantly, the large red-shifted emission band of AuO, reported in the presence of human insulin fibrils, and which was projected as its major advantage over ThT, is not observed in the presence of BSA fibrils as well as fibrils from other proteins, such as lysozyme, human serum albumin, and β-lactoglobulin. Thus, our results provide information on the universal applicability of the distinctive and claimed-to-be-advantageous photophysical features reported for AuO in human insulin fibrils towards fibrils from other proteins. Time-resolved fluorescence measurements also support the proposition of a strong interaction of AuO with native BSA. Additionally, tryptophan emission of the protein has been explored to further elucidate the binding mechanism of AuO with native BSA. Evaluation of thermodynamic parameters revealed that the binding of AuO with native BSA involved positive enthalpy and entropy changes, suggesting dominant contributions from hydrophobic and electrostatic interactions toward the association of AuO with native BSA. Molecular docking calculations have been performed to identify the principal binding location of AuO in native BSA.
- Published
- 2016
65. A Simple and Sensitive Method for Auramine O Detection Based on the Binding Interaction with Bovin Serum Albumin
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Hui Zhang, Ruilin Duan, Jidong Yang, Yusheng Yuan, Xin Huang, Shaopu Liu, Jingjing Yan, and Xiaoli Hu
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Absorption spectroscopy ,Serum albumin ,Analytical chemistry ,02 engineering and technology ,01 natural sciences ,Analytical Chemistry ,Hydrophobic effect ,chemistry.chemical_compound ,Limit of Detection ,Fluorescence Resonance Energy Transfer ,Detection limit ,Quenching (fluorescence) ,Auramine O ,biology ,010401 analytical chemistry ,Osmolar Concentration ,Serum Albumin, Bovine ,Hydrogen-Ion Concentration ,021001 nanoscience & nanotechnology ,Fluorescence ,0104 chemical sciences ,Spectrometry, Fluorescence ,chemistry ,Ionic strength ,Benzophenoneidum ,biology.protein ,0210 nano-technology ,Hydrophobic and Hydrophilic Interactions ,Protein Binding - Abstract
A simple, rapid and effective method for auramine O (AO) detection was proposed by fluorescence and UV-Vis absorption spectroscopy. In the BR buffer system (pH 7.0), AO had a strong quenching ability to the fluorescence of bovin serum albumin (BSA) by dynamic quenching. In terms of the thermodynamic parameters calculated as ΔH > 0 and ΔS > 0, the resulting binding of BSA and AO was mainly attributed to the hydrophobic interaction forces. The linearity of this method was in the concentration range from 0.16 to 50 μmol L(-1) with a detection limit of 0.05 μmol L(-1). Based on fluorescence resonance energy transfer (FRET), the distance r (1.36 nm) between donor (BSA) and acceptor (AO) was obtained. Furthermore, the effects of foreign substances and ionic strength were evaluated under the optimum reaction conditions. BSA as a selective probe could be applied to the analysis of AO in medicines with satisfactory results.
- Published
- 2016
66. Sequestration of dyes from artificially prepared textile effluent using RSM-CCD optimized hybrid backbone based adsorbent-kinetic and equilibrium studies
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Vaishali Pruthi, Sukriti, Jaspreet Kaur Bhatia, Prerna Anand, Amritpal Singh Chadha, Jitender Sharma, and Balbir Singh Kaith
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Langmuir ,Reaction mechanism ,Environmental Engineering ,Polymers ,02 engineering and technology ,Management, Monitoring, Policy and Law ,010402 general chemistry ,01 natural sciences ,Polyvinyl alcohol ,Waste Disposal, Fluid ,symbols.namesake ,chemistry.chemical_compound ,Adsorption ,X-Ray Diffraction ,Polymer chemistry ,Spectroscopy, Fourier Transform Infrared ,Freundlich equation ,Response surface methodology ,Coloring Agents ,Waste Management and Disposal ,Tartrates ,Chemistry ,Rhodamines ,Polysaccharides, Bacterial ,technology, industry, and agriculture ,Temperature ,Langmuir adsorption model ,Sorption ,General Medicine ,Hydrogen-Ion Concentration ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Kinetics ,Chemical engineering ,Benzophenoneidum ,Polyvinyl Alcohol ,Textile Industry ,symbols ,Gelatin ,0210 nano-technology ,Water Pollutants, Chemical - Abstract
Present work reports the synthesis of semi-Interpenetrating Network Polymer (semi-IPN) using Gelatin-Gum xanthan hybrid backbone and polyvinyl alcohol in presence of l-tartaric acid and ammonium persulphate as the crosslinker-initiator system. Reaction parameters were optimized with Response Surface Methodology (RSM) in order to maximize the percent gel fraction of the synthesized sample. Polyvinyl alcohol, l-Tartaric acid, ammonium persulphate, reaction temperature, time and pH of the reaction medium were found to make an impact on the percentage gel fraction obtained. Incorporation of polyvinyl alcohol chains onto hybrid backbone and crosslinking between the different polymer chains were confirmed through techniques like FTIR, SEM-EDX and XRD. Semi-IPN was found to be very efficient in the removal of cationic dyes rhodamine-B (70%) and auramine-O (63%) from a mixture with an adsorbent dose of 700 mg, initial concentration of rhodamine-B 6 mgL-1 and auramine-O 26 mgL-1, at an time interval of 22-25 h and 30 °C temp. Further to determine the nature of adsorption Langmuir and Freundlich adsorption isotherm models were studied and it was found that Langmuir adsorption isotherm was the best fit model for the removal of mixture of dyes. Kinetic studies for the sorption of dyes favored the reaction mechanism to occur via a pseudo second order pathway with R2 value about 0.99.
- Published
- 2016
67. LED fluorescence microscopy in the diagnosis of tuberculosis: Fading and restaining of smears for external quality assessment
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Arnaldo Andrés Jara, Mario José Matteo, Alejandro Souto, María Susana Imaz, Ana Alicia Etchart, Gabriela María Santiso, Mónica Aranibar, Viviana Caserío, Sonia Allassia, Viviana Izquierdo, A. Togneri, Mónica García, Noemí Gomez, Sandra Fajardo, Silvia Pellegrino, Sandra Vilche, Sebastián Pérez Catalán, Carlos Pellegrini, Lidia Wolff, Alba Marisa Gunia, Mónica Boutonnet, María Virginia Gustincic, Graciela Kozicky, Carina Sacramone, Susana Poggi, and Daniel Eletti
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0301 basic medicine ,Microbiology (medical) ,Pathology ,medicine.medical_specialty ,Quality Assurance, Health Care ,030106 microbiology ,Evaluación externa de calidad ,Preservation, Biological ,Argentina ,Microbiology ,03 medical and health sciences ,Predictive Value of Tests ,External quality assessment ,medicine ,Fluorescence microscope ,Humans ,Tuberculosis ,Fading ,Single-Blind Method ,Lighting ,Fluorescent Dyes ,Cryopreservation ,Observer Variation ,Photobleaching ,Staining and Labeling ,business.industry ,Sputum ,Temperature ,Reproducibility of Results ,General Medicine ,Specimen Quality ,Microscopy, Fluorescence ,Benzophenoneidum ,Feasibility Studies ,Radiology ,business ,LED fluorescence microscopy ,Microscopía de fluorescencia LED - Abstract
Blinded rechecking is a method proposed for external quality assurance (EQA) of auramine-stained acid-fast bacilli (AFB) smears using fluorescence microscopy (FM), however, this procedure is not well developed and slides fading over time could compromise its implementation. Since bleaching of fluorescent molecules involves temperature-dependent chemical reactions, it is likely that low temperatures could slow down this process. We stored auramine-stained slides under different environmental conditions, including −20 °C, and examined them over time. The slides stored in all the environments faded. At −20 °C, fading was not reduced in relation to room temperature. Restaining and re-examining smears after five months showed that the slides containing saliva and storage at −20 °C were associated with failure in AFB reappearance. In conclusion, the practice of freezing slides until they are viewed should be discouraged as it has a negative effect on blinded rechecking by reducing reading concordance after restaining. Specimen quality should be considered when interpreting FM-EQA results.
- Published
- 2015
68. Catalytic Effects of Different Heparin Analogs on the Hydrolysis of Auramine O
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Yijun Chen, Yunmian He, and Jianxin Li
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Chemical structure ,Biomedical Engineering ,Biophysics ,Bioengineering ,Fondaparinux ,Catalysis ,Biomaterials ,chemistry.chemical_compound ,Hydrolysis ,Polysaccharides ,Benzophenone ,medicine ,Organic chemistry ,Molecular Structure ,Auramine O ,Heparin ,Anticoagulants ,Hydrogen-Ion Concentration ,Molecular Weight ,Kinetics ,chemistry ,Benzophenoneidum ,Ionic strength ,medicine.drug - Abstract
Glycosaminoglycans, such as heparin, are a class of biomaterials with a variety of important biological functions. They were found to catalyze the hydrolysis of 4,4'-(imidocarbonyl)-bis(N,N-dimethylaniline) monohydrochloride to 4,4'-bis(dimethy-lamino) benzophenone, but the catalytic mechanism of this interesting reaction is poorly understood, mainly due to the structural complexity of polysaccharides. In order to study such an unusual reaction, a pentasaccharide, fondaparinux, with defined chemical structure was chosen as a probe to investigate the hydrolytic characteristics, along with other heparin analogs. The hydrolytic reaction was catalyzed by fondaparinux, low-molecular-weight heparins, heparin and different desulfated heparins at various rates. The present results demonstrated that the length of polysaccharide chain, the N- or O-sulfo groups are critical to the hydrolysis of 4,4'-(imidocarbonyl)-bis(N,N-dimethy-laniline) monohydrochloride in addition to pH and ionic strength, which provides new insights into the catalytic phenomenon of polysaccharides.
- Published
- 2011
69. Monoolein cubic phase containing acidic proteinoid: pH-dependent release
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Jin-Chul Kim and Taek Kwan Kwon
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Amaranth Dye ,Inorganic chemistry ,Biological Availability ,Pharmaceutical Science ,Amaranth ,Aquaporins ,Phase Transition ,Glycerides ,chemistry.chemical_compound ,Proteinoid ,Leucine ,Phase (matter) ,Drug Discovery ,Pharmacology ,Aspartic Acid ,Drug Carriers ,Auramine O ,Organic Chemistry ,Cationic polymerization ,Proteins ,Hydrogen-Ion Concentration ,Alkali metal ,Methylene Blue ,chemistry ,Distilled water ,Benzophenoneidum ,Acids ,Methylene blue - Abstract
Objective: Monoolein (MO) cubic phase containing acidic proteinoid was prepared for a pH-dependent release. Methods: The acidic proteinoid was prepared by a thermal-condensation reaction of Asp and Leu (9.85/0.15 in molar ratio). To prepare MO cubic phase, molten MO was hydrated with the proteinoid solution in distilled water. For pH-dependent release experiment, amaranth was included as an anionic dye, and either auramine O or methylene blue was contained as a cationic dye. Results: The release of amaranth from the cubic phase was promoted under neutral and alkali conditions, possibly because of electrostatic repulsions between the anionic dye and the ionized carboxylic group of the acidic proteinoid. On the contrary, the releases of auramine O and methylene blue were suppressed under neutral and alkali conditions, probably because of electrostatic interactions between the cationic dyes and the ionized carboxylic group. Conclusion: The acidic proteinoid is believed to control the releases in response to ...
- Published
- 2010
70. Reactive Dynamics in Confined Liquids: Interfacial Charge Effects on Ultrafast Torsional Dynamics in Water Nanodroplets
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Stephen R. Meech, Jamie Conyard, Ismael A. Heisler, Minako Kondo, and Jasmine P. H. Rivett
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Time Factors ,Friction ,Diffusion ,Static Electricity ,Analytical chemistry ,Micelle ,Polyethylene Glycols ,Surface-Active Agents ,symbols.namesake ,chemistry.chemical_compound ,Pulmonary surfactant ,Phase (matter) ,Materials Chemistry ,Reactive dye ,Physical and Theoretical Chemistry ,Micelles ,Dioctyl Sulfosuccinic Acid ,Aqueous solution ,Molecular Structure ,Smoluchowski coagulation equation ,Auramine O ,Water ,Nanostructures ,Surfaces, Coatings and Films ,Spectrometry, Fluorescence ,chemistry ,Benzophenoneidum ,Chemical physics ,symbols - Abstract
The excited-state dynamics of a reactive dye molecule, auramine O, have been studied in nanoscale water droplets stabilized by a nonionic surfactant. Spectral dynamics were measured as a function of the radius of the water nanodroplet with 50 fs time resolution using time-resolved fluorescence up-conversion method. Qualitatively, the effect of confinement is to dramatically slow the rate of the reaction compared to that of bulk water. Data were quantitatively analyzed using the one-dimensional generalized Smoluchowski equation assuming a time-dependent diffusion coefficient. The results were contrasted with our earlier analysis of auramine O in aqueous nanodroplets stabilized by the ionic surfactant AOT. The excited-state reaction is slower in the nonionic surfactant, showing that interfacial charge is not required to suppress reactions in nanoscale water droplets. The location of the dye in the heterogeneous micelle is investigated by comparing the absorption spectra of AO in the micelle with those of a water- polyethyleneglycol mixture (to mimic the surfactant head group). The results suggest that the charged dye is located in the water phase.
- Published
- 2009
71. Specific detection and quantification of culturable and non-culturable mycobacteria in metalworking fluids by fluorescence-based methods
- Author
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Jagjit S. Yadav, Suresh B. Selvaraju, and Izhar U. H. Khan
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Detection limit ,Bacteriological Techniques ,Microbial Viability ,Staining and Labeling ,biology ,Colony Count, Microbial ,Industrial Waste ,biology.organism_classification ,Sensitivity and Specificity ,Applied Microbiology and Biotechnology ,Viable but nonculturable ,Mycobacterium ,Microbiology ,Staining ,Microscopy, Fluorescence ,Benzophenoneidum ,Microscopy ,Fluorescence microscope ,Mycobacterium immunogenum ,Water Microbiology ,Bacteria - Abstract
Aims: To optimize and evaluate fluorescence microscopy assays for specific assessment of mycobacteria and co-contaminants, including culturable and non-culturable sub-populations, in metalworking fluids (MWF). Methods and Results: Auramine-O-rhodamine (AR) staining and LIVE/DEAD BacLight™ Bacterial Viability staining (L/D staining) were adapted and evaluated for detection/quantification and differentiation (viable vs non-viable) of the MWF-associated mycobacteria and the background bacterial flora, respectively. The AR staining method was found to be specific to MWF mycobacteria with a minimum detection limit of 10 cells ml−1 and was comparable to the QPCR in quantification efficiency in MWF matrix. The L/D staining-based microscopy allowed differential quantification of viable vs non-viable cells. In general, a 3-log difference was observed between the L/D microscopy count and culture count accounting for the presence of non-culturable fraction in the bacterial population in in-use MWF. Conclusions: The optimized AR staining- and the L/D staining-based microscopy methods have the potential for rapid, specific and differential assessment (viable vs non-viable) of MWF-associated mycobacteria and co-contaminants in field MWF. Significance and Impact of the study: Early detection of MWF mycobacteria by rapid, low-cost, less-skill intensive and culture-independent fluorescence-based microscopy methods will facilitate timely intervention to protect the machine workers from occupational hazards.
- Published
- 2008
72. Use of Light‐Emitting Diode Fluorescence Microscopy to Detect Acid‐Fast Bacilli in Sputum
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Elizabeth Wasserman, Wendy Brittle, Nulda Beyers, Katrien Painczyk, Dick van Soolingen, Ben J. Marais, Rob Warren, and Anneke C. Hesseling
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Adult ,Microbiology (medical) ,Pathology ,medicine.medical_specialty ,Microbiological culture ,Tuberculosis ,Sensitivity and Specificity ,Mycobacterium tuberculosis ,chemistry.chemical_compound ,Microscopy ,Fluorescence microscope ,Humans ,Medicine ,Coloring Agents ,Tuberculosis, Pulmonary ,Observer Variation ,Bacteriological Techniques ,Staining and Labeling ,biology ,Auramine O ,business.industry ,Sputum ,Equipment Design ,Gold standard (test) ,biology.organism_classification ,medicine.disease ,Cross-Sectional Studies ,Infectious Diseases ,Microscopy, Fluorescence ,chemistry ,Benzophenoneidum ,medicine.symptom ,business - Abstract
Background Fluorescence microscopy offers well-described benefits, compared with conventional light microscopy, for the evaluation of sputum smear samples for tuberculosis. However, its use in resource-limited settings has been limited by the high cost of the excitatory light source. We evaluated the diagnostic performance of fluorescence microscopy, using novel light-emitting diode (LED) technology as an alternative to the conventional mercury vapor lamp (MVP). Methods Routinely collected sputum specimens from persons suspected to have tuberculosis who attended community clinics were stained with auramine O and were evaluated using 2 different excitatory light sources (MVP and LED); these specimens were then Ziehl-Neelsen stained and reexamined using light microscopy. Two microscopists independently evaluated all smears. Bacterial culture provided the gold standard. Results Of the 221 sputum specimens evaluated, 36 (16.3%) were positive for Mycobacterium tuberculosis by culture. Sensitivity and specificity documented for the different modalities were 84.7% and 98.9%, respectively, for the LED assessment; 73.6% and 99.8%, respectively, for the MVP assessment; and 61.1% and 98.9%, respectively, for light microscopy. kappa values for interreader variation were 0.87 for the LED assessment, 0.79 for the MVP assessment, and 0.77 for light microscopy. The mean time to read a negative smear was 1.4 min with fluorescence microscopy and 3.6 min with light microscopy, reflecting a time savings of 61% with fluorescence microscopy. Conclusion LED fluorescence microscopy provides a reliable alternative to conventional methods and has many favorable attributes that facilitate improved, decentralized, diagnostic services.
- Published
- 2008
73. The photo-oxidative destruction of C.I. Basic Yellow 2 using UV/S2O8 2− process in an annular photoreactor
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N. Daneshvar, Mohammad Hossein Rasoulifard, Aligholi Niaei, Soheil Aber, and D. Salari
- Subjects
Environmental Engineering ,Photochemistry ,Ultraviolet Rays ,Photodissociation ,Analytical chemistry ,Color ,Quantum yield ,General Medicine ,Oxidative phosphorylation ,Hydrogen-Ion Concentration ,Volumetric flow rate ,chemistry.chemical_compound ,C.I. basic yellow 2 ,chemistry ,Benzophenoneidum ,Peroxydisulfate ,Photochemical degradation ,Oxidation-Reduction ,Ultraviolet radiation - Abstract
The photo-oxidative decolorization of C. I. Basic Yellow 2 (BY2), was investigated using UV radiation in the presence of peroxydisulfate (S(2)O(8)(2-)) in an annular photoreactor at different conditions. S(2)O(8)(2-) and UV-light showed negligible effect when they were used independently. Removal efficiency of BY2 was sensitive to the operational parameters such as initial concentrations of S(2)O(8)(2-), BY2 and pH. The conversion ratios of BY2 at the volumetric flow rates of 330, 500 and 650 mLmin(- 1) were 84%, 78%, 69% in 1 h, respectively. The results showed that in the presence of S(2)O(8)(2-), the photooxidation quantum yield obtained higher than direct photolysis quantum yield, suggesting that photodecay of BY2 was dominated by photooxidation. The electrical energy per order (EE/O) values for decolorization of BY2 solution was calculated. Results show that applying an optimum peroxydisulfate concentration can reduce the EE/O.
- Published
- 2008
74. Nontuberculous Mycobacterial Infection in Patients With Cystic Fibrosis: A Multicenter Prevalence Study
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Concepción Prados, Rosa Girón, Luis Máiz, Isabel Barrio, Antonio Salcedo, and M. Teresa Martínez
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Adult ,Male ,medicine.medical_specialty ,Tuberculosis ,Adolescent ,Cystic Fibrosis ,Mycobacterium abscessus ,Azithromycin ,Cystic fibrosis ,Mycobacterium tuberculosis ,Young Adult ,Anti-Infective Agents ,Internal medicine ,Prevalence ,Humans ,Medicine ,Child ,Prospective cohort study ,Tuberculosis, Pulmonary ,Aged ,Mycobacterium Infections ,biology ,business.industry ,General Medicine ,Middle Aged ,biology.organism_classification ,medicine.disease ,Benzophenoneidum ,Immunology ,Sputum ,Female ,Nontuberculous mycobacteria ,medicine.symptom ,business ,medicine.drug - Abstract
Objective To determine the prevalence of nontuberculous mycobacterial infection in patients with cystic fibrosis. Patients and methods We performed a prospective study in which patients with cystic fibrosis were followed for 2 years; the patients were recruited from specialized units and were all over 6 years old. Sputum samples collected every 6 months were stained with auramine-rhodamine and cultures were prepared with a liquid and a solid medium. When stains or cultures were positive for nontuberculous mycobacteria, 1 or 2 additional sputum samples were obtained from the patients, who were monitored closely to assess the need for specific treatment. We assessed the following clinical variables: age, sex, presence of pancreatic insufficiency, use of aerosol antibiotic therapy, and long-term azithromycin and inhaled or oral corticosteroid therapies. Results A total of 220 patients (119 women) with a mean age of 22.62 years (range, 6-74 years) were enrolled; of these23.6% were receiving azithromycin. We prepared 1303 sputum samples for mycobacterial growth (range per patient, 4-68 samples); 65 samples from a total of 17 patients(7.72%) were positive: 17 by auramine-rhodamine staining and 48 by culture. Eighty-eight culture samples were contaminated and Mycobacterium tuberculosis was not isolated in any of the cases. The mycobacteria isolated were avium complex (n=10), abscessus (n=6), and fortuitum (n=1). Two or more positive cultures were obtained in 9 patients, 5 of whom experienced clinical deterioration and were prescribed specific treatment. No significant differences in clinical variables were found between patients with nontuberculous mycobacteria and those without. Conclusions The prevalence of nontuberculous mycobacterial infection in patients with cystic fibrosis was not very high (7.72%), perhaps because azithromycin interfered with the growth of these bacteria. Patients with repeat isolations of mycobacteria should be monitored closely.
- Published
- 2008
75. Adsorptive removal of Auramine-O: Kinetic and equilibrium study
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Vimal Chandra Srivastava, Nitin Kumar Agarwal, and Indra Deo Mall
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Langmuir ,Time Factors ,Environmental Engineering ,Health, Toxicology and Mutagenesis ,Mineralogy ,Coal Ash ,Diffusion ,symbols.namesake ,chemistry.chemical_compound ,Adsorption ,medicine ,Environmental Chemistry ,Freundlich equation ,Waste Management and Disposal ,Auramine O ,Langmuir adsorption model ,Sorption ,Hydrogen-Ion Concentration ,Pollution ,Carbon ,Gibbs free energy ,Kinetics ,Models, Chemical ,chemistry ,Benzophenoneidum ,symbols ,Thermodynamics ,Particulate Matter ,Nuclear chemistry ,Activated carbon ,medicine.drug - Abstract
Present study deals with the adsorption of Auramine-O (AO) dye by bagasse fly ash (BFA) and activated carbon-commercial grade (ACC) and laboratory grade (ACL). BFA is a solid waste obtained from the particulate collection equipment attached to the flue gas line of the bagasse fired boilers of cane sugar mills. Batch studies were performed to evaluate the influences of various experimental parameters like initial pH (pH(0)), contact time, adsorbent dose and initial concentration (C(0)) for the removal of AO. Optimum conditions for AO removal were found to be pH(0) approximately 7.0 and equilibrium time approximately 30 min for BFA and approximately 120 min for activated carbons. Optimum BFA, ACC and ACL dosages were found to be 1, 20 and 2g/l, respectively. Adsorption of AO followed pseudo-second order kinetics with the initial sorption rate for adsorption on BFA being the highest followed by those on ACL and ACC. The sorption process was found to be controlled by both film and pore diffusion with film diffusion at the earlier stages followed by pore diffusion at the later stages. Equilibrium isotherms for the adsorption of AO on BFA, ACC and ACL were analyzed by Freundlich, Langmuir, Dubinin-Radushkevich, and Temkin isotherm equations using linear correlation coefficient. Langmuir isotherm gave the best correlation of adsorption for all the adsorbents studied. Thermodynamic study showed that adsorption of AO on ACC (with a more negative Gibbs free energy value) is more favoured. BFA which was used without any pretreatment showed high surface area, pore volume and pore size exhibiting its potential to be used as an adsorbent for the removal of AO.
- Published
- 2007
76. Simultaneous staining of sputum smears for acid-fast and lipid-containing Myobacterium tuberculosis can enhance the clinical evaluation of antituberculosis treatments
- Author
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Lize van der Merwe, Sven O. Friedrich, Peter R. Donald, Xavier A. Kayigire, and Andreas H. Diacon
- Subjects
Microbiology (medical) ,Bacilli ,Tuberculosis ,Time Factors ,medicine.drug_class ,Immunology ,Antibiotics ,Antitubercular Agents ,Colony Count, Microbial ,Adamantane ,Microbiology ,Mycobacterium tuberculosis ,South Africa ,Predictive Value of Tests ,Oxazines ,medicine ,Humans ,Tuberculosis, Pulmonary ,Fluorescent Dyes ,Colony-forming unit ,biology ,Sputum ,Lipid Droplets ,biology.organism_classification ,medicine.disease ,Ethylenediamines ,Bacterial Load ,Staining ,Infectious Diseases ,Treatment Outcome ,Microscopy, Fluorescence ,Benzophenoneidum ,Drug Therapy, Combination ,medicine.symptom ,Drug Monitoring ,Rifampin ,Rifampicin ,medicine.drug - Abstract
Dormant, slow-growing, antibiotic-tolerant Mycobacterium tuberculosis undermine the shortening of tuberculosis treatment to less than 6 months and are thought to be characterised by intracellular lipid bodies. Antibiotic effects on such persisting bacilli escape evaluation as they cannot be readily cultured. We identified cells containing lipid bodies in sputum smears from 86 newly diagnosed pulmonary tuberculosis patients and monitored these cells daily in 42 patients over the first 14 days of treatment with rifampicin, the experimental compound SQ-109, or both agents combined. Counts of Nile-Red-positive lipid-body containing cells were correlated with those of Auramine-O-positive cells and colony forming units of viable Mycobacterium tuberculosis on agar plates. Rifampicin but not SQ-109 significantly reduced colony forming units but all treatments distinctively and significantly changed the proportions of lipid body-containing bacilli and viable Mycobacterium tuberculosis. Monitoring lipid-body containing bacilli in sputum during treatment with experimental antituberculosis regimens may identify putative treatment-shortening regimens.
- Published
- 2015
77. A Testing Scheme for the Detection of Mycobacterium Avium subsp. Paratuberculosis in Bovine Feces Utilizing the ESP Para-JEM Liquid Culture System
- Author
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Beverly Byrum, William P. Shulaw, Sreekumari Rajeev, Roy D. Berghaus, and Yan Zhang
- Subjects
DNA, Bacterial ,0301 basic medicine ,040301 veterinary sciences ,Liquid culture ,030106 microbiology ,Cattle Diseases ,Paratuberculosis ,Pilot Projects ,Polymerase Chain Reaction ,Stain ,Microbiology ,0403 veterinary science ,Feces ,03 medical and health sciences ,mental disorders ,medicine ,Animals ,Coloring Agents ,Fluorescent Dyes ,General Veterinary ,biology ,Rhodamines ,04 agricultural and veterinary sciences ,biology.organism_classification ,medicine.disease ,Culture Media ,Staining ,Mycobacterium avium subsp. paratuberculosis ,Benzophenoneidum ,Cattle ,Subculture (biology) ,Mycobacterium - Abstract
A testing scheme for the detection of Mycobacterium avium subsp. paratuberculosis (MAP) in broth cultures of bovine fecal samples carried out in ESP para-JEM System was evaluated. The scheme included acid-fast staining (on signal-positive and signal-negative samples), and confirmation by PCR for 2 MAP-specific targets and subculture of all acid-fast positive PCR-negative samples. Two hundred and fifty bovine fecal samples were evaluated for the presence of MAP using this scheme. Thirty-seven (15%) of 250 fecal samples had a positive culture result when the proposed testing scheme was used, compared to 14 (6%) positive results when using the standard ESP para-JEM protocol (requiring samples to have a positive signal from the system, a positive acid-fast stain, and a positive IS 900 PCR result), and 20 (8%) positives when conventional culture was performed on Herrold egg yolk (HEY) media. A preliminary comparison of real-time and conventional PCR on DNA extracted from 15 MAP-positive broth cultures by 3 different protocols suggested that conventional PCR may be a better choice for the confirmation of the presence of MAP in the liquid cultures than real-time PCR.
- Published
- 2006
78. Clinical correlates of tuberculosis co-infection in HIV-infected children hospitalized in Peru
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Richard A. Oberhelman, Vivian Kawai, Robert H. Gilman, Maria E. Ramirez-Cardich, Maria E. Castillo, and Christian T. Bautista
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Male ,Microbiology (medical) ,medicine.medical_specialty ,Tuberculosis ,Population ,HIV Infections ,Polymerase Chain Reaction ,03 medical and health sciences ,0302 clinical medicine ,Acquired immunodeficiency syndrome (AIDS) ,Immunopathology ,Internal medicine ,Weight Loss ,Peru ,medicine ,Humans ,030212 general & internal medicine ,Child ,Sida ,education ,Tuberculosis, Pulmonary ,Children ,0303 health sciences ,education.field_of_study ,AIDS-Related Opportunistic Infections ,Staining and Labeling ,biology ,030306 microbiology ,business.industry ,Infant ,HIV ,Mycobacterium tuberculosis ,General Medicine ,biology.organism_classification ,medicine.disease ,Culture Media ,3. Good health ,Infectious Diseases ,Clinical research ,El Niño ,Benzophenoneidum ,Child, Preschool ,Immunology ,HIV-1 ,Female ,Viral disease ,business - Abstract
Summary Introduction In developing countries, tuberculosis (TB) is responsible for almost 250000 deaths among children yearly. Active TB in children with human immunodeficiency virus (HIV) infection is difficult to diagnose and progresses rapidly to death. The aim of this preliminary study was to investigate the prevalence and clinical correlates of TB-related illness among HIV-infected children admitted to an infectious diseases ward in Peru, a country where TB is highly endemic. Method Forty-seven HIV-infected children admitted for a suspected infectious process in a Peruvian hospital were investigated for evidence of clinical tuberculosis by auramine stain, culture, and polymerase chain reaction (PCR) of clinical specimens. Results Eight children (17%) had evidence of tuberculosis, including five with positive cultures and three with positive PCR tests only. Weight loss was the only feature associated with a positive test for tuberculosis. Radiological changes were very common in both TB-positive and TB-negative groups and these changes were not useful to identify TB-positive cases. Conclusions Weight loss may be used to identify high-risk HIV positive children who require more aggressive evaluation for tuberculosis. Radiological changes were common in both TB-positive and TB-negative groups.
- Published
- 2006
79. Replication and Long-Term Persistence of Bovine and Human Strains of Mycobacterium avium subsp. paratuberculosis within Acanthamoeba polyphaga
- Author
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John Hermon-Taylor, Roger W. Pickup, Glenn Rhodes, Manuela Mura, Liz McMinn, Tim J. Bull, Hugh F. Evans, and Karim Sidi-Boumedine
- Subjects
Time Factors ,Cattle Diseases ,Paratuberculosis ,Acanthamoeba ,Human pathogen ,Lobosea ,Polymerase Chain Reaction ,Applied Microbiology and Biotechnology ,Microbial Ecology ,law.invention ,Microbiology ,Crohn Disease ,law ,medicine ,Animals ,Humans ,In Situ Hybridization ,Polymerase chain reaction ,Subclinical infection ,Staining and Labeling ,Ecology ,biology ,Rhodamines ,biology.organism_classification ,medicine.disease ,Virology ,Mycobacterium avium subsp. paratuberculosis ,Benzophenoneidum ,DNA Transposable Elements ,Protozoa ,Cattle ,Digestive System ,Food Science ,Biotechnology ,Mycobacterium - Abstract
Free-living protists are ubiquitous in the environment and form a potential reservoir for the persistence of animal and human pathogens. Mycobacterium avium subsp. paratuberculosis is the cause of Johne's disease, a systemic infection accompanied by chronic inflammation of the intestine that affects many animals, including primates. Most humans with Crohn's disease are infected with this chronic enteric pathogen. Subclinical infection with M. avium subsp. paratuberculosis is widespread in domestic livestock. Infected animals excrete large numbers of robust organisms into the environment, but little is known about their ability to replicate and persist in protists. In the present study we fed laboratory cultures of Acanthamoeba polyphaga with bovine and human strains of M. avium subsp. paratuberculosis . Real-time PCR showed that the numbers of the pathogens fell over the first 4 to 8 days and recovered by 12 to 16 days. Encystment of the amoebic cultures after 4 weeks resulted in a 2-log reduction in the level of M. avium subsp. paratuberculosis , which returned to the original level by 24 weeks. Extracts of resection samples of human gut from 39 patients undergoing abdominal surgery were fed to cultures of A. polyphaga. M. avium subsp. paratuberculosis detected by nested IS 900 PCR with amplicon sequencing and visualized by IS 900 in situ hybridization and auramine-rhodamine staining was found in cultures derived from 13 of the patients and was still present in the cultures after almost 4 years of incubation. Control cultures were negative. M. avium subsp. paratuberculosis has the potential for long-term persistence in environmental protists.
- Published
- 2006
80. Auramine Orange Stain With Fluorescence Microscopy is a Rapid and Sensitive Technique for the Detection of Cervical Lymphadenitis Due to Mycobacterial Infection Using Fine Needle Aspiration Cytology: A Case Series
- Author
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D. Gregory Farwell, Alan G. Cheng, S. Nicholas Agoff, and Anthony Chang
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Time Factors ,Tuberculosis ,Biopsy, Fine-Needle ,Tuberculosis, Lymph Node ,Sensitivity and Specificity ,Stain ,Diagnosis, Differential ,Mycobacterium tuberculosis ,03 medical and health sciences ,0302 clinical medicine ,Cytology ,Biopsy ,medicine ,Fluorescence microscope ,Humans ,Coloring Agents ,030223 otorhinolaryngology ,medicine.diagnostic_test ,biology ,business.industry ,Middle Aged ,Mycobacterium avium Complex ,biology.organism_classification ,medicine.disease ,Fine-needle aspiration ,Microscopy, Fluorescence ,Otorhinolaryngology ,Benzophenoneidum ,030220 oncology & carcinogenesis ,Female ,Surgery ,Nontuberculous mycobacteria ,business - Abstract
OBJECTIVE: We sought to evaluate the effectiveness of the auramine orange (AO) stain in diagnosing mycobacterial cervical adenitis (MCA) from fine needle aspiration (FNA) cytology. METHODS: A retrospective review of 19 patients evaluated at 2 urban hospitals from 2000 to 2003 for suspected MCA. FNA specimens were inoculated to culture media and had direct smears stained by the auramine acid fast method.RESULTS: Mycobacteria were identified in 16 (84.2%) of 19 AO-stained FNA specimens, with results available within 4 hours. Corresponding cultures were positive for mycobacteria in 12 specimens, 9 tuberculous and 3 nontuberculous, and grew Mycobacterium tuberculosis from the 3 AO-negative specimens. Three of the 4 patients with negative cultures had previously taken anti-mycobacterial medications.CONCLUSION: The AO stain with fluorescence microscopy is a sensitive and rapid method for detecting tuberculous and nontuberculous mycobacteria. It is a valuable tool for the otolaryngologists and pathologists in th...
- Published
- 2005
81. Comparison of the COBAS AMPLICOR MTB and BDProbeTec ET assays for detection of Mycobacterium tuberculosis in respiratory specimens
- Author
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A. van Belkum, Wil H. F. Goessens, Hubert P. Endtz, J.G.M. Koeleman, P de Man, A. Luijendijk, R. te Witt, and Medical Microbiology & Infectious Diseases
- Subjects
Microbiology (medical) ,Pathology ,medicine.medical_specialty ,Tuberculosis ,Sensitivity and Specificity ,Mycobacterium tuberculosis ,SDG 3 - Good Health and Well-being ,medicine ,Cobas amplicor ,Humans ,Mycobacterium Infections ,biology ,Staining and Labeling ,Becton dickinson ,Sputum ,Mycobacteriology and Aerobic Actinomycetes ,Nucleic acid amplification technique ,medicine.disease ,biology.organism_classification ,equipment and supplies ,bacterial infections and mycoses ,Virology ,Culture Media ,Mycobacterium tuberculosis complex ,Benzophenoneidum ,Clinical diagnosis ,Reagent Kits, Diagnostic ,medicine.symptom ,Bronchoalveolar Lavage Fluid ,Nucleic Acid Amplification Techniques - Abstract
The performances of the BDProbeTec ET (Becton Dickinson) and COBAS AMPLICOR MTB (Roche) were retrospectively evaluated for detecting Mycobacterium tuberculosis complex in various respiratory specimens. The BACTEC and MGIT liquid culture system (Becton Dickinson) was used as a reference method. A total of 824 respiratory specimens, comprised of sputa, bronchoalveolar lavage fluid, and bronchial and tracheal aspirates from 580 patients, were evaluated. Out of 824 clinical specimens, 109 specimens from 43 patients were culture positive for M. tuberculosis . Of these 109 specimens, 67 were smear positive, 85 were positive by the COBAS AMPLICOR MTB test, and 94 were positive by the BDProbeTec ET. Of the 715 culture-negative specimens, 17 were positive by the auramine staining, 11 were positive by the COBAS AMPLICOR MTB test, and 12 were positive by the BDProbeTec ET. After discrepancy analysis and review of the patients' clinical data, 130 specimens from 50 patients were considered “true-positive” specimens. This resulted in the following sensitivities: microscopy, 61.5%; COBAS AMPLICOR MTB test, 78.0%; and BDProbeTec ET, 86.2%. The specificities of each system, based on the clinical diagnosis, were 99.7% for microscopy, 99.9% for the COBAS AMPLICOR MTB test, and 99.9% for the BDProbeTec ET. The data presented represent a considerable number of specimens evaluated with a considerable number of culture- and auramine-positive and culture-positive and auramine-negative results and therefore give a realistic view of how the data should be interpreted in a daily routine situation. Specifically, the data with regard to the culture-positive and auramine-negative specimens are useful, because in a routine situation, auramine-negative specimens are sometimes accepted, on clinical indications, to be analyzed by an amplification method.
- Published
- 2005
82. An operational study comparing microscopes and staining variations for tuberculosis LED FM
- Author
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Mohammad Anwar Hossain, K. J. M. Aung, M Gumusboga, A. Van Deun, B. C. de Jong, and M H Khan
- Subjects
Pulmonary and Respiratory Medicine ,Pathology ,medicine.medical_specialty ,Microscope ,Staining technique ,Sensitivity and Specificity ,law.invention ,Tuberculosis diagnosis ,law ,Predictive Value of Tests ,Microscopy ,Medicine ,Tuberculosis ,False Positive Reactions ,Organic Chemicals ,False Negative Reactions ,Staining and Labeling ,business.industry ,Sputum ,Reproducibility of Results ,Standard technique ,Staining ,Infectious Diseases ,Microscopy, Fluorescence ,Benzophenoneidum ,Tuberculosis control ,business ,Nuclear medicine ,Field conditions - Abstract
Setting Tuberculosis control projects, Damien Foundation Bangladesh. Objectives To compare transmitted fluorescence (Olympus CX21™/FRAEN FluoLED™) with epi-fluorescence (Zeiss Primostar iLED™) light-emitting diode microscopes (LED-FM) and various auramine staining and destaining/counterstaining techniques for the detection of acid-fast bacilli. Design Multicentre blinded reading of routine smears on both types of microscopes using different staining techniques in multiple phases. LED-FM rechecking of discordant series with and without restaining to calculate operating characteristics. Results Among 64 874 smears, both instruments detected 9.6% positives. Compared to the standard technique, the stronger auramine-O formulation did not perform better. Thiazine red counterstaining tended to yield more false-positive as well as false-negative errors. Combined destaining/counterstaining (sensitivity 93%, positive predictive value [PPV] 98%) proved significantly less effective. Both destaining with 1% hydrochloric acid (HCl) and 10% alcohol and the standard 0.5% HCl and 70-95% alcohol were equally accurate (sensitivity 95-96%, PPV 99%). The sturdiness of the microscopes in field conditions was sub-optimal: only 5/16 instruments did not break down. Conclusions Both microscopes performed equally well. The standard staining technique is as good as the more complicated and expensive variations. A destaining solution containing only 10% alcohol works perfectly well. The inferior quality of LED-FM microscope components is an obstacle to FM expansion.
- Published
- 2014
83. Simultaneous ultrasound-assisted ternary adsorption of dyes onto copper-doped zinc sulfide nanoparticles loaded on activated carbon: optimization by response surface methodology
- Author
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Mehrorang Ghaedi, Arash Asfaram, Shaaker Hajati, Ali Akbar Bazrafshan, and Alireza Goudarzi
- Subjects
Langmuir ,Central composite design ,Analytical chemistry ,Sulfides ,Analytical Chemistry ,symbols.namesake ,chemistry.chemical_compound ,Adsorption ,medicine ,Freundlich equation ,Ultrasonics ,Response surface methodology ,Coloring Agents ,Instrumentation ,Spectroscopy ,Analysis of Variance ,Chemistry ,Temperature ,Langmuir adsorption model ,Hydrogen-Ion Concentration ,Zinc sulfide ,Atomic and Molecular Physics, and Optics ,Methylene Blue ,Kinetics ,Erythrosine ,Benzophenoneidum ,Zinc Compounds ,Charcoal ,symbols ,Nanoparticles ,Copper ,Activated carbon ,medicine.drug - Abstract
The simultaneous and competitive ultrasound-assisted removal of Auramine-O (AO), Erythrosine (Er) and Methylene Blue (MB) from aqueous solutions were rapidly performed onto copper-doped zinc sulfide nanoparticles loaded on activated carbon (ZnS:Cu-NP-AC). ZnS:Cu nanoparticles were studied by FESEM, XRD and TEM. First, the effect of pH was optimized in a one-at-a-time procedure. Then the dependency of dyes removal percentage in their ternary solution on the level and magnitude of variables such as sonication time, initial dyes concentrations and adsorbent dosage was fully investigated and optimized by central composite design (CCD) under response surface methodology (RSM) as well as by regarding desirability function (DF) as a good and general criterion. The good agreement found between experimental and predicted values supports and confirms the suitability of the present model to predict adsorption state. The applied ultrasound strongly enhanced mass transfer process and subsequently performance. Hence, a small amount of the adsorbent (0.04 g) was capable to remove high percentage of dyes, i.e. 100%, 99.6% and 100% for MB, AO and Er, respectively, in very short time (2.5 min). The experimental equilibrium data fitting to Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models showed that the Langmuir model applies well for the evaluation and description of the actual behavior of adsorption. The small amount of proposed adsorbent (0.015 g) was applicable for successful removal of dyes (RE>99.0%) in short time (2.5 min) with high adsorption capacity in single component system (123.5 mg g(-1) for MB, 123 mg g(-1) for AO and 84.5 mg g(-1) for Er). Kinetics evaluation of experiments at various time intervals reveals that adsorption processes can be well predicated and fitted by pseudo-second-order and Elovich models.
- Published
- 2014
84. Application of ultrasonic radiation for simultaneous removal of auramine O and safranine O by copper sulfide nanoparticles: experimental design
- Author
-
Hossein Sadeghi, Raham Armand, Allahdad Fatehi, Mohammad Ali Khodadoust, Mehrorang Ghaedi, and Saeid Khodadoust
- Subjects
Central composite design ,Sonication ,Analytical Chemistry ,chemistry.chemical_compound ,Adsorption ,X-Ray Diffraction ,medicine ,Ultrasonics ,Response surface methodology ,Instrumentation ,Spectroscopy ,Analysis of Variance ,Chromatography ,Aqueous solution ,Auramine O ,Atomic and Molecular Physics, and Optics ,Copper sulfide ,chemistry ,Benzophenoneidum ,Nanoparticles ,Phenazines ,Copper ,Activated carbon ,medicine.drug ,Nuclear chemistry - Abstract
In this study, copper sulfide nanoparticles loaded on activated carbon (CuS-NP-AC) were synthesized by novel, low cost and green approach and characterized using SEM and XRD. The application of this material for the simulations removal of auramine O (AO) and safranine O (SO) from aqueous solutions was investigated. The dependency of removal percentages to variables such as pH, initial dyes concentration, adsorbent dosage, sonication time and sonication temperature were studied with response surface methodology (RSM) by considering the desirability function (DF). The quadratic model between the dependent and the independent variables was built. The proposed method showed good agreement between the experimental data and predictive value, and it has been successfully employed to removal of AO and SO in aqueous media. The studied adsorbent (0.06 g of CuS-NP-AC) was capable of high percentage removal (99.8% and 99.5%) of 18 mg mL(-1) AO and SO in short time (7.0 min).
- Published
- 2014
85. Improving acid-fast fluorescent staining for the detection of mycobacteria using a new nucleic acid staining approach
- Author
-
Howard M. Shapiro, Anne J. Lenaerts, and Gavin J. Ryan
- Subjects
Microbiology (medical) ,DNA, Bacterial ,Time Factors ,Immunology ,Signal-To-Noise Ratio ,Microbiology ,Stain ,Mycobacterium tuberculosis ,Microscopy, Electron, Transmission ,Predictive Value of Tests ,Microscopy ,medicine ,Fluorescence microscope ,Humans ,Organic Chemicals ,Tuberculosis, Pulmonary ,Fluorescent Dyes ,biology ,Staining and Labeling ,Rhodamines ,Sputum ,Reproducibility of Results ,biology.organism_classification ,Fluorescence ,Molecular biology ,Staining ,RNA, Bacterial ,Infectious Diseases ,Microscopy, Fluorescence ,Benzophenoneidum ,Nucleic acid ,medicine.symptom - Abstract
Acid fast staining of sputum smears by microscopy remains the prevalent method for detecting Mycobacterium tuberculosis. The sensitivity of microscopy using acid fast stains requires 10(4) bacilli per ml of sputum. Although fluorescent acid fast stains, such as Auramine-O, show improved sensitivity, almost half of culture-positive TB cases are currently estimated to remain smear-negative. These current diagnosis problems provide impetus for improving staining procedures. We evaluated a novel fluorescent acid-fast staining approach using the nucleic acid-binding dye SYBR(®) Gold on mycobacterial in vitro cultures. The SYBR(®) Gold stain detected 99% of MTB in both actively replicating aerobic and non-replicating hypoxic cultures. Transmission light microscopy with Ziehl-Neelsen fuchsin, and fluorescence microscopy with Auramine-O or Auramine-rhodamine detected only 54%-86% of MTB bacilli. SYBR(®) Gold fluoresces more intensely than Auramine-O, and is highly resistant to fading. The signal to noise ratio is exceptionally high due to a >1000-fold enhanced fluorescence after binding to DNA/RNA, thereby reducing most background fluorescence. Although cost and stability of the dye may perhaps limit its clinical use at this time, these results warrant further research into more nucleic acid dye variants. In the meantime, SYBR(®) Gold staining shows great promise for use in numerous research applications.
- Published
- 2014
86. Toxicity of imine-iminium dyes and pigments: electron transfer, radicals, oxidative stress and other physiological effects
- Author
-
Peter, Kovacic and Ratnasamy, Somanathan
- Subjects
Indoles ,Rhodamines ,Pheophytins ,Trityl Compounds ,Isoindoles ,Electron Transport ,Methylene Blue ,Disease Models, Animal ,Oxidative Stress ,Benzophenoneidum ,Pyocyanine ,Rosaniline Dyes ,Animals ,Humans ,Imines ,Coloring Agents ,Reactive Oxygen Species - Abstract
Although conjugation is well known as an important contributor to color, there is scant recognition concerning involvement of imine and iminium functions in the physiological effects of this class of dyes and pigments. The group includes the dyes methylene blue, rhodamine, malachite green, fuchsin, crystal violet, auramine and cyanins, in addition to the pigments consisting of pyocyanine, phthalocyanine and pheophytin. The physiological effects consist of both toxicity and beneficial aspects. The unifying theme of electron transfer-reactive oxygen species-oxidative stress is used as the rationale in both cases. Toxicity is frequently prevented or alleviated by antioxidants. The apparent dichotomy of methylene blue action as both oxidant and antioxidant is rationalized based on similar previous cases. This mechanistic approach may have practical benefit. This review is important in conveying, for the first time, a unifying mechanism for toxicity based on electron transfer-reactive oxygen species-oxidative stress arising from imine-iminium.
- Published
- 2014
87. The CyScope® Fluorescence Microscope, a Reliable Tool for Tuberculosis Diagnosis in Resource-Limited Settings
- Author
-
Charles Félix Bilong Bilong, Leopold Gustave Lehman, Françoise Ngo Sack, and Arlette L. Ngapmen Yamadji
- Subjects
Pathology ,medicine.medical_specialty ,Time Factors ,Tuberculosis ,Sensitivity and Specificity ,Mycobacterium tuberculosis ,fluids and secretions ,Tuberculosis diagnosis ,Virology ,parasitic diseases ,medicine ,Fluorescence microscope ,Humans ,False Negative Reactions ,Staining and Labeling ,biology ,Rhodamines ,business.industry ,Sputum ,Articles ,bacterial infections and mycoses ,biology.organism_classification ,medicine.disease ,Fluorescence ,Staining ,Infectious Diseases ,Microscopy, Fluorescence ,Benzophenoneidum ,Parasitology ,medicine.symptom ,business ,Limited resources - Abstract
Poor laboratory equipment and few human resources have made it difficult to implement microscopic diag- nosis of pulmonary tuberculosis (TB) on a large scale basis worldwide. Three hundred sputum samples from patients in Cameroon were studied by using the CyScope ® , a new light-emitting, diode-based, fluorescence microscope, to compare auramine-rhodamine fluorescence with the conventional Ziehl-Neelsen staining method. Five fluorescence protocols were tested to reduce manipulation time. Smear positivity for acid-fast bacilli with the Ziehl-Neelsen staining method was 27.7% (83 of 300) compared with 33.3% (100 of 300) with the fluorescent method. Staining time with the modified fluo- rescence protocol could be reduced from 21 minutes to 10 minutes. This study confirmed that the fluorescence staining method is more sensitive than the Ziehl-Neelsen staining method. It is suggested that the training of laboratory techni- cians on fluorescence microscopy should be scaled up for increased disease control.
- Published
- 2010
88. Evaluation of a Rapid Fluorescent Staining Method for Detection of Mycobacteria in Clinical Specimens
- Author
-
Karen C. Carroll, Kim Dionne, Nicole Parrish, Annie Hedgepeth, and Cindy Hendry
- Subjects
Microbiology (medical) ,Time Factors ,Tuberculosis ,Sensitivity and Specificity ,Fluorescence ,Mycobacterium ,Microbiology ,chemistry.chemical_compound ,medicine ,Humans ,Rapid stain ,Fluorescent Dyes ,Staining and Labeling ,biology ,Auramine O ,Differential staining ,Mycobacteriology and Aerobic Actinomycetes ,biology.organism_classification ,medicine.disease ,Molecular biology ,Staining ,chemistry ,Benzophenoneidum ,Fluorescent staining ,Bacteria - Abstract
Rapid detection of mycobacterial disease is essential. Using multiple specimen types and concentrations of mycobacteria, we compared two commercial auramine O stains. The more rapid stain permitted consistent acid-fast bacillus quantitation and exhibited less debris staining, and the staining procedure required less time (∼2 min) to perform. These results suggest that the rapid stain may be more cost-effective and efficient for use in clinical laboratories.
- Published
- 2009
89. Cytological diagnosis of pulmonary nocardiosis in an immunocompromised patient
- Author
-
V Kaushal, Deepinder Chhina, Rajesh Mahajan, Ramesh Kumar, and Harpreet Kaur
- Subjects
Microbiology (medical) ,medicine.medical_specialty ,pulmonary ,medicine.medical_treatment ,Pulmonary nocardiosis ,Biopsy, Fine-Needle ,lcsh:QR1-502 ,Nocardia Infections ,Chest pain ,Nocardia ,lcsh:Microbiology ,Immunocompromised Host ,Fine needle aspiration cytology ,Fine-needle aspiration cytology ,medicine ,Humans ,Lung ,nocardiosis ,Lung Diseases, Fungal ,Staining and Labeling ,immunosuppression ,business.industry ,Nocardiosis ,Immunosuppression ,Middle Aged ,medicine.disease ,Surgery ,Staining ,medicine.anatomical_structure ,Benzophenoneidum ,Female ,Radiology ,medicine.symptom ,Vasculitis ,business - Abstract
We report a case of pulmonary nocardiosis in an immunosuppressed patient having vasculitis who presented with fever, cough and chest pain. A suspicion of nocardiosis was made on auramine O staining of material procured by CT guided fine needle aspiration cytology right lung. Modified Ziehl-Neelsen staining was useful in confirming the diagnosis. The patient showed remarkable recovery after treatment with co-trimoxazole. Quick identification of this uncommon pathogen in the cytological material using special stains helped in timely diagnosis and successful treatment of the patient.
- Published
- 2008
90. Clinical Evaluation of a Commercial Ligase-Based Gene Amplification Method for Detection of Mycobacterium tuberculosis
- Author
-
Antonio Orduña, Miguel Ángel Bratos, A. San Miguel, P. L. Alonso, and A Rodríguez Torres
- Subjects
Microbiology (medical) ,medicine.medical_specialty ,Time Factors ,Tuberculosis ,Sensitivity and Specificity ,Microbiology ,Mycobacterium tuberculosis ,Medical microbiology ,Predictive Value of Tests ,Positive predicative value ,Gene duplication ,medicine ,Humans ,False Positive Reactions ,Tuberculosis, Pulmonary ,chemistry.chemical_classification ,Bacteriological Techniques ,DNA ligase ,Staining and Labeling ,biology ,Gene Amplification ,Reproducibility of Results ,General Medicine ,biology.organism_classification ,medicine.disease ,Molecular biology ,Infectious Diseases ,chemistry ,Benzophenoneidum ,Evaluation Studies as Topic ,Clinical evaluation ,Bacteria - Abstract
The purpose of this study was to evaluate the clinical usefulness of a commercial ligase-based gene amplification method (LCx Mycobacterium tuberculosis test; Abbott Laboratories, USA) for detection of Mycobacterium tuberculosis. The tuberculosis infection rate among clinical samples was 10.6%. The sensitivity, specificity, and positive and negative predictive values were 23.5%, 100%, 100%, and 91.7%, respectively, with the fluorochrome auramine stain; 32.4%, 100%, 100%, and 92.6%, respectively, with culture; and 76.5%, 95.8%, 68.4% and 97.2%, respectively, with the gene amplification method. When only samples from patients without current or previous treatment were studied, the sensitivity was 36.4% with the auramine stain, 63.6% with culture, and 100% with the gene amplification assay. The mean treatment time for culture-negative and assay-negative samples was greater than that of culture-negative and assay-positive samples. The LCx Mycobacterium tuberculosis test is a sensitive method for detection and identification of Mycobacterium tuberculosis. It produces few false-positive results. However, as it can remain positive after the culture becomes negative, it is not recommended for evaluation of treatment efficiency.
- Published
- 1998
91. Detection of Mycobacterial Infections Using the Dieterle Stain
- Author
-
Barbara Marks, David M. Parham, Gordon E. Schutze, John Brady, Hazel V. Horn, and Robert Seibert
- Subjects
Adult ,Male ,Pathology ,medicine.medical_specialty ,Adolescent ,Nocardia Infections ,Biology ,Sensitivity and Specificity ,Stain ,Pathology and Forensic Medicine ,Microbiology ,Diagnosis, Differential ,Surgical pathology ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Child ,Coloring Agents ,Fluorescent Antibody Technique, Indirect ,Retrospective Studies ,Mycobacterium Infections ,030219 obstetrics & reproductive medicine ,Rhodamines ,Differential staining ,Nocardiosis ,Cat-Scratch Disease ,Infant ,Cat-scratch disease ,General Medicine ,medicine.disease ,biology.organism_classification ,Staining ,Benzophenoneidum ,Child, Preschool ,030220 oncology & carcinogenesis ,Pediatrics, Perinatology and Child Health ,Female ,Differential diagnosis ,Bacteria - Abstract
Retrospective review comparing the modified Dieterle stain with standard acid-fast stains was performed on seven surgical pathology cases that contained culture-positive mycobacteria infections. Tissues examined comprised cervical and submandibular lymph nodes and soft tissues of the face and chest. Modified Dieterle staining was performed on paraffin-embedded tissue sections, and the results were compared with those of hematoxylineosin stains and auramine-rhodamines and carbol-fuchsin acid-fast stains. The acid-fast stain showed organisms in three of seven cases on initial review and five of seven cases on retrospective review; the auramine-rhodamine stain retrospectively revealed organisms in five cases. In contrast, the Dieterle stain showed organisms in all seven sections on retrospective examination. Dieterle stains revealed either beaded bacilli or nocardia-like filamentous organisms, sometimes with abundant granular debris possibly representing degenerative organisms. In three cases in which bacteria were readily apparent with the Dieterle stain, only rare organisms could be identified with the acid-fast stain. The modified Dieterle stain was more sensitive than the acid-fast stain in the identification of mycobacteria in pediatric specimens, and its use is recommended in cases with necrotizing granulomas. However, its specificity is limited by morphologic similarities of the organisms to those of nocardiosis and cat scratch disease.
- Published
- 1998
92. Free radicals generated in yeast by the Salmonella test-negative carcinogens benzene, urethane, thiourea and auramine O
- Author
-
Robert H. Schiestl and Richard J. Brennan
- Subjects
Free Radicals ,Health, Toxicology and Mutagenesis ,Radical ,Saccharomyces cerevisiae ,medicine.disease_cause ,Urethane ,Superoxide dismutase ,chemistry.chemical_compound ,Salmonella ,Genetics ,medicine ,Animals ,Molecular Biology ,Carcinogen ,Fluorescent Dyes ,Recombination, Genetic ,Auramine O ,biology ,Mutagenicity Tests ,Superoxide Dismutase ,Thiourea ,Benzene ,Methane sulfonate ,Free Radical Scavengers ,Fluoresceins ,Free radical scavenger ,Acetylcysteine ,Oxidative Stress ,Biochemistry ,chemistry ,Benzophenoneidum ,Carcinogens ,biology.protein ,Oxidation-Reduction ,Genotoxicity ,Mutagens - Abstract
A large fraction of carcinogens score negative in short-term genotoxicity assays such as the Salmonella reverse mutation (Ames) assay. More information is needed about the mechanism of action of such Salmonella-negative carcinogens. Many Salmonella-negative carcinogens induce deletions due to intrachromosomal recombination in Saccharomyces cerevisiae with an apparent threshold. We have previously shown that the Salmonella-negative carcinogens cadmium, aniline, chloroform and carbon tetrachloride generate free radical species in S. cerevisiae. We have further investigated the possible generation of intracellular free radical species by the diverse Salmonella-negative carcinogens benzene, urethane, thiourea and auramine O. The toxicity and recombinagenicity of thiourea and auramine O was reduced in the presence of the free radical scavenger N-acetyl cysteine. N-acetyl cysteine did not protect against toxicity or recombination induced by the Salmonella-positive carcinogens ethyl methane sulfonate, methyl methane sulfonate or nitroquinoline-N-oxide. A strain deficient in the enzyme superoxide dismutase, which catalyses the dismutation of superoxide anion radical, was hypersensitive to killing by benzene, urethane and thiourea. The sod- strain was only slightly more sensitive to the Salmonella-positive carcinogens. Intracellular oxidation of the free radical-sensitive reporter compound dichlorofluorescin diacetate was increased in yeast cultures exposed to benzene, urethane and auramine O; again, the Salmonella mutagens had no effect on oxidation of the dye. These data show that free radical species are produced in Saccharomyces cerevisiae following exposure to benzene, urethane, thiourea and auramine O, and suggest a possible role for oxidative stress is recombination induced by these carcinogens.
- Published
- 1998
93. Evaluation of auramine genotoxicity in primary rat and human hepatocytes and in the intact rat
- Author
-
Roberta Canonero, Roberto Carrozzino, Francesca Mattioli, Luigi Robbiano, Antonietta Martelli, Marco Cavanna, and Giulia Brambilla Campart
- Subjects
Male ,DNA damage ,Health, Toxicology and Mutagenesis ,Urinary Bladder ,DNA Fragmentation ,Biology ,medicine.disease_cause ,Rats, Sprague-Dawley ,Genetics ,medicine ,Animals ,Humans ,Coloring Agents ,Cells, Cultured ,Carcinogen ,Micronucleus Tests ,Mucous Membrane ,Cell Death ,Anatomy ,Molecular biology ,Rats ,Comet assay ,medicine.anatomical_structure ,Liver ,Benzophenoneidum ,Hepatocyte ,Micronucleus test ,Toxicity ,DNA fragmentation ,Genotoxicity ,DNA Damage ,Mutagens - Abstract
Auramine, a dye previously found to be a liver carcinogen in both mice and rats, was evaluated for its DNA-damaging and clastogenic activities in primary cultures of rats and human hepatocytes and for the induction of DNA single-strand breaks in the liver and urinary bladder mucosa of intact rats. A similar dose-dependent frequency of DNA fragmentation was revealed by the alkaline elution technique in metabolically competent primary cultures of both rat and human hepatocytes exposed for 20 h to subtoxic concentrations ranging from 10 to 32 microM. In contrast, neither rat nor human hepatocytes displayed an increased frequency of micronuclei after a 48-h exposure to the same auramine concentrations. In rats given a single oral dose of 125, 250 or 500 mg kg-1 auramine, the Comet assay revealed a significant increase in the frequency of DNA lesions in the liver and in the urinary bladder mucosa, the effect being slightly more marked in the liver. Taken as a whole and compared with previous findings, these results suggest that auramine is biotransformed into reactive species in target organs of both rats and humans, and that this dye might play by itself the main role in the increased incidence of bladder cancer which has been judged as causally related to its manufacture.
- Published
- 1998
94. Reticulocytes and Reticulated Platelets: Simultaneous Measurement in Whole Blood by Flow Cytometry
- Author
-
Anna Caldini, A. R. Miele, Bartolini L, Alessandra Fanelli, A. Del Genovese, A. Buggiani, A Ermini, and Stefano Rapi
- Subjects
Blood Platelets ,Pathology ,medicine.medical_specialty ,Reticulocytes ,Clinical Biochemistry ,Reticulated platelets ,Biology ,Flow cytometry ,Reticulocyte Count ,Reticulocyte ,Reticulocyte count ,medicine ,Humans ,Platelet ,Benzothiazoles ,Thrombopoiesis ,Coloring Agents ,Fluorescent Dyes ,Whole blood ,medicine.diagnostic_test ,Platelet Count ,Biochemistry (medical) ,Linear amplification ,General Medicine ,Flow Cytometry ,Hematopoiesis ,Thiazoles ,medicine.anatomical_structure ,Benzophenoneidum ,Evaluation Studies as Topic ,Quinolines ,Biomedical engineering - Abstract
Reticulated platelets are a fraction of newly released circulating elements characterized by a residual amount of RNA. It has been suggested that the reticulated platelet count, providing an estimate of thrombopoiesis in the same way as erythrocyte reticulocyte count is a measure of erythropoiesis, may be useful in the study of thrombocytopenic disorders. Reticulated red cells and platelets can be analyzed by flow cytometry using specific stains for nucleic acids such as Thiazole Orange and Auramine-O. The aim of our work was to perform the simultaneous evaluation of reticulated elements in whole blood using a standard flow cytometer and to correlate the results obtained with a dedicated cytometer. A group of 14 patients with abnormal absolute reticulocyte counts (range 1.1–11%) and a group of 41 patients showing a platelet discrimination error when analyzed with a dedicated flow cytometer (Sysmex R1000) were enrolled. Linear amplification of both scatter and fluorescence was used to perform reticulocyte count. A gate was set on platelet dimensions, and logarithmic amplification of scatter and fluorescence was used to count reticulated platelets. A good correlation was obtained both for results of reticulocyte count (r2 = 0.9825) and for reticulated platelets (r2 = 0.8717) between our method and those using dedicated instruments. These data show that reticulated platelet count may be easily introduced in clinical laboratories that routinely perform reticulocyte count by flow cytometry.
- Published
- 1998
95. Histologic Parameters Predictive of Mycobacterial Infection
- Author
-
Glenn D. Roberts, Yi-Wei Tang, Gary W. Procop, Jeffrey L. Myers, and Xiaotian Zheng
- Subjects
Pathology ,medicine.medical_specialty ,Auramine-rhodamine stain ,Biopsy ,Inflammation ,Malignancy ,Mycobacterium ,medicine ,Humans ,Coloring Agents ,Mycobacterium Infections ,Granuloma ,Staining and Labeling ,medicine.diagnostic_test ,Rhodamines ,business.industry ,Cancer ,General Medicine ,medicine.disease ,Staining ,Benzophenoneidum ,Giant cell ,Acute Disease ,medicine.symptom ,business - Abstract
Tissue specimens from a wide variety of anatomic locations are frequently examined for mycobacteria using a combination of cultures and special stains. Auramine-rhodamine (AR) staining is a sensitive method for detecting acid-fast bacilli (AFB) in tissue sections. We reviewed 85 AR-positive and 275 randomly selected AR-negative biopsy specimens collected during the past 2 years at the Mayo Clinic, Rochester, Minn. Pathologic diagnoses and culture results were also reviewed. Biopsy specimens containing necrotizing granulomas yielded the highest positivity rate for AFB (61 [47.7%]), followed by nonnecrotizing granulomas (14 [17.7%]). Poorly formed granulomas (5 [16.1%]) and acute inflammation (5 [15.6%]) were less frequently positive. Cases with fibrotic or hyalinized granulomas, nonspecific chronic inflammation, nonspecific reactive or reparative changes, no significant histologic abnormality, or malignancy failed to disclose AFB. These specimens, which were consistently negative for AFB, were responsible for 25% of the samples submitted. Of the 360 tissue specimens submitted, 166 had a corresponding mycobacterial culture. Mycobacteria were cultured only from the biopsy specimens that contained necrotizing granulomas (38.2%), nonnecrotizing granulomas (32.4%), poorly formed granulomas (30.0%), or acute inflammation (15.8%). Tissues with fibrotic or hyalinized granulomas, nonspecific chronic inflammation, nonspecific reactive or reparative changes, no significant histologic abnormality, or malignancy failed to yield positive cultures. These data suggest that biopsy specimens with these latter diagnoses are inappropriate specimens for mycobacterial culture or AR staining.
- Published
- 1998
96. UV-fixed-thick-blotch preparation improves sensitivity of auramine staining
- Author
-
M. J. Martinez-Lirola, M. J. Munoz-Davila, M. A. Cejudo-García, [Cejudo-García,MA, Muñoz-Davila,MJ, and Martínez-Lirola,MJ] Microbiology Laboratory, Biotechnology Clinic Management Unit, Torrecárdenas Hospital Complex, Almería, Spain
- Subjects
Microbiology (medical) ,Anatomy::Fluids and Secretions::Bodily Secretions::Sputum [Medical Subject Headings] ,Esputo ,Sensitivity and Specificity ,Benzofenoneido ,Diseases::Bacterial Infections and Mycoses::Bacterial Infections::Gram-Positive Bacterial Infections::Actinomycetales Infections::Mycobacterium Infections::Tuberculosis [Medical Subject Headings] ,Specimen Handling ,Microbiology ,Mycobacterium ,Chemicals and Drugs::Organic Chemicals::Amines::Aniline Compounds::Benzophenoneidum [Medical Subject Headings] ,Manejo de especímenes ,fluids and secretions ,Tuberculosis diagnosis ,mental disorders ,Humans ,Tuberculosis ,Bacteriological Techniques ,Staining and Labeling ,biology ,Organisms::Bacteria::Gram-Positive Bacteria::Gram-Positive Rods::Gram-Positive Asporogenous Rods::Gram-Positive Asporogenous Rods, Regular::Mycobacteriaceae::Mycobacterium [Medical Subject Headings] ,Mycobacterial culture ,Sputum ,Mycobacteriology and Aerobic Actinomycetes ,biology.organism_classification ,bacterial infections and mycoses ,Molecular biology ,Staining ,Analytical, Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Diagnostic Techniques and Procedures::Clinical Laboratory Techniques::Specimen Handling [Medical Subject Headings] ,Técnicas bacteriológicas ,Mycobacterium tuberculosis complex ,Benzophenoneidum ,Nontuberculous mycobacteria ,Analytical, Diagnostic and Therapeutic Techniques and Equipment::Diagnosis::Diagnostic Techniques and Procedures::Clinical Laboratory Techniques::Microbiological Techniques::Bacteriological Techniques [Medical Subject Headings] ,psychological phenomena and processes - Abstract
We describe here a very simple modification of the auramine staining procedure based on preparation of a UV-fixed thick blotch which allowed us to reach an overall sensitivity of 0.82 (592 acid-fast bacillus [AFB]-positive specimens/722 initial respiratory specimens with positive mycobacterial culture) and sensitivities of 0.93 (526 AFB-positive specimens/564 culture-positive specimens) for Mycobacterium tuberculosis complex and 0.42 (66 AFB-positive specimens/158 culture-positive specimens) for nontuberculous mycobacteria.
- Published
- 2013
97. Differences in the detection of Cryptosporidium and Isospora (Cystoisospora) oocysts according to the fecal concentration or staining method used in a clinical laboratory
- Author
-
Neuza Maria Alcântara-Neves, Moacir P. Silva, Márcia Cristina Aquino Teixeira, Adson S. Martins, Ricardo Riccio Oliveira, Renata K. N. R. Silva, Flávia Thamiris Figueiredo Pacheco, and Neci Matos Soares
- Subjects
Diarrhea ,Veterinary medicine ,Cystoisospora ,animal diseases ,Coloring agents ,Cryptosporidiosis ,Cryptosporidium ,Centrifugation ,Acetates ,Microbiology ,chemistry.chemical_compound ,Feces ,Fixatives ,fluids and secretions ,Safranin ,Formaldehyde ,parasitic diseases ,Humans ,Coloring Agents ,Ecology, Evolution, Behavior and Systematics ,Acquired Immunodeficiency Syndrome ,biology ,Isospora ,Staining and Labeling ,Isosporiasis ,biology.organism_classification ,Staining ,chemistry ,Benzophenoneidum ,Phenazines ,Parasitology ,Indicators and Reagents - Abstract
Despite the availability of many parasitological methods for detection of Cryptosporidium and Isospora (Cystoisospora) belli in fecal samples, there are uncertainties about the accuracy of these techniques in laboratory practice. In this study, 27 formalin-fixed positive stool samples for Cryptosporidium and 15 for I. belli were analyzed by 2 concentration methods, sedimentation by centrifugation (SC) and formalin-ethyl acetate (FE), and by 3 tintorial techniques, modified Ziehl-Neelsen (ZN), safranin (SF), and auramine (AR). No significant differences were observed on Cryptosporidium identification between concentration methods, while a significantly higher number of I. belli oocysts (P0.0001) was detected in fecal smears concentrated by the SC than by the FE method. Fecal samples processed by FE produced a median oocyst loss to the fatty ring of 34.8% for Cryptosporidium and 45.4% for I. belli. However, FE concentration provided 63% of Cryptosporidium and 100% of I. belli slides classified as superior for microscopic examination. Regarding the efficiency of staining methods, a more significant detection of Cryptosporidium oocysts was observed in fecal smears stained by ZN (P0.01) or AR (P0.05) than by the SF method. Regular to high-quality slides for microscopic examination were mostly observed in fecal smears stained with AR or ZN for Cryptosporidium and with SF or ZN for I. belli. This study suggests a great variability in oocyst power detection by routine parasitological methods, and that the most frequent intestinal coccidians in humans have specific requirements for concentration and staining.
- Published
- 2013
98. Preparation and evaluation of a novel molecularly imprinted SPE monolithic capillary column for the determination of auramine O in shrimp
- Author
-
Jiangmei, Li, Haiyun, Zhai, Zuanguang, Chen, Qing, Zhou, Zhenping, Liu, and Zihao, Su
- Subjects
Molecular Imprinting ,Benzophenoneidum ,Decapoda ,Solid Phase Extraction ,Animals ,Chromatography, High Pressure Liquid - Abstract
A novel method combining molecular imprinting and SPE was developed in a capillary column for the determination of auramine O in shrimp. The capillary monolithic column was prepared by UV-initiated in situ polymerization, using auramine O as template and methacrylic acid and ethylene dimethacrylate as functional monomer and cross-linker, respectively. The properties of the prepared capillary monolithic column were investigated under the optimized conditions coupled with HPLC, and then the morphologies of the inner polymers were characterized by SEM. The calibration curve was expressed as A = 103C + 19.8 (r = 0.9992) with a linear range of 0.25-25.0 μg/mL, and the recoveries of auramine O at different concentrations in shrimp ranged from 90.5 to 92.4% with RSDs ranging from 2.1 to 4.4%. The capacities of the molecularly imprinted polymer and nonimprinted polymer columns were 0.722 and 0.147 μg/mg, respectively, and the LOD (S/N = 3) of auramine O in shrimp was 17.85 μg/kg. Under the selected conditions, the enrichment factors obtained were higher than 70-fold. The results indicate that the prepared molecularly imprinted capillary monolithic column was reliable and applicable to the analysis of auramine O in shrimp.
- Published
- 2013
99. Interference of blood leucocytes in the measurements of immature red cells (reticulocytes) by two different (semi-) automated flow-cytometry technologies
- Author
-
A. Kirsch, S. Serke, Dieter Huhn, J.L. Vives-Corrons, and N. Villamor
- Subjects
Biology ,Flow cytometry ,Automation ,Reticulocyte Count ,Reticulocyte ,Oxazines ,Leukocytes ,medicine ,Humans ,False Positive Reactions ,Benzothiazoles ,Fluorescent Dyes ,Staining and Labeling ,medicine.diagnostic_test ,Immunomagnetic Separation ,DNA ,Hematology ,Flow Cytometry ,Thiazole orange ,Molecular biology ,Staining ,Clinical Practice ,Thiazoles ,medicine.anatomical_structure ,Benzophenoneidum ,Cells reticulocytes ,Quinolines ,RNA ,Software - Abstract
Flow cytometrical methods have been introduced recently as an alternative to the enumeration of reticulocytes by microscopy. Two of these methods have gained widespread use in haematological practice; the multiparametric flow cytometer using thiazole orange staining (Retic-Count, FACScan) and the single-application reticulocyte counter using auramine-O staining (R-series, Sysmex). Several studies have emphasized the excellent correlations between microscopy and these techniques. The purpose of our study has been to examine the specificity of these automated devices with regard to cells classified as 'reticulocytes' and the effect that this may have on measures of reticulocyte maturity. Our results indicate that the specificity of reticulocyte measurements by both the Sysmex R-1000/-3000 and the Retic-Count system is relatively low. This is due to the presence of leucocytes amongst cells classified as reticulocytes. These leucocytes display intense staining with either dye, leading to an erroneous estimation of RMI (thiazole orange) and high fluorescence count (R-1000/-3000). This error is directly correlated with the leucocyte count. The basis for reticulocyte identification should be improved before automated estimation of reticulocyte maturation can be used in clinical practice.
- Published
- 1996
100. [Determination of ten basic dyes in meat products by ultra fast liquid chromatography-ion trap time of flight mass spectrometry]
- Author
-
Donglei, Zhang, Lina, Wang, Xiaozhen, Chen, Jin, Wang, Hui, Cao, and Liying, Huang
- Subjects
Meat Products ,Spectrometry, Mass, Electrospray Ionization ,Benzophenoneidum ,Rhodamines ,Swine ,Animals ,Cattle ,Food Contamination ,Coloring Agents ,Chromatography, Liquid - Abstract
A method was developed for the simultaneous determination of 10 basic dyes in meat products using ultra fast liquid chromatography-ion trap time of flight mass spectrometry (LC-IT-TOF-MS). The target analytes were separated at a flow rate of 0.2 mL/min on a Waters Acquity UPLC BEH C18 (100 mm x 2.1 mm, 1.7 microm) column with a gradient elution. The mobile phase was 5 mmol/L ammonium acetate-acetonitrile (containing 0.1% (v/v) formic acid). The identification and quantification were achieved in positive ion mode with electro spray ionization source. The samples were extracted with a simple procedure using acetonitrile and cleaned up by weak cation exchange (Oasis WCX) solid phase extraction column. Ten basic dyes were determined by LC-IT-TOF-MS, and quantified by external standard method. The developed method showed a good linearity over the wide range of 1.0 - 100.0 microg/L, and the relative standard deviations (n = 7) were less than 8.54%. The average recoveries of the ten basic dyes at three levels (2, 10 and 25 microg/kg) were ranged from 65.39% to 119.18%. Therefore, this method, owing to its simplicity, rapidity and high sensitivity, has a good applicability to the simultaneous determination of dye residues in meat products.
- Published
- 2012
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