Comparison between ziehl-neelsen staining and fluorescent staining of sputum samples to detect acid fast bacilli in suspected case of pulmonary tuberculosis at tertiary care hospital, Amreli, Gujarat

In India, Tuberculosis (TB) is one of the major community health problems.Pulmonary tuberculosis (PTB) is a respiratory disease. Causative organism for this is acid fast bacilli known as . It is the most ordinary disease affecting the lower socio-economic class in developing countries. Microbiological diagnosis is the heart for the effective treatment of pulmonary TB (PTB). The look forrapid and efficient method has resulted in several staining techniques. Objective of the study was to compare the results of ZN stain (RNTCP) with fluorescent stain by use of microscopy. The study was carried out in Microbiology Department, SMCGH, Amreli. 350 sputum samples (Spot and early morning sample) collected from 175 suspected case of the pulmonary tuberculosis. All 350 samples were processed by ZN stain and Fluorescent stain to detect acid fast bacilli. By use of microscope, the results of the stained smears were given according to RNTCP guideline.Out of 350 sputum smears, 52 (14.85%) and 61 (17.4%) were positive by ZN and FM staining respectively. Males are predominantly affected than females. Majority of the patients were in age above 50 years. Early morning samples were more reliable than spot samples for detection of acid fast bacilli for ZN stain, but not for fluorescent stain.Fluorescent staining with LED microscopy was more efficient than ZN staining for detection of acid fast bacilli from sputum smear.

Synthesis and Spectral Characterisation of (E)-3-(3-(4 (Dimethylamino)Phenyl)Acrylo-yl)-4-Hydroxy-2H-Chromen-2-One and Their Antibacterial Activity and Acetylcholinesterase Inhibition

A new coumarin derivative, (E)-3-(3-(4-(dimethylamino) phenyl) acrylo-yl)-4-hydroxy-2H-chromen-2-one (3), was synthesized by the condensation of 3-acetyl-4-hydroxycoumarin (1) with 4-N,N-dimethylaminobenzaldehyde (2) in the presence of piperidine in ethanol. The structure of the synthesized compound was characterized using spectroscopic data (IR and 1H NMR) and elemental analysis. The antimicrobial properties and acetylcholinesterase inhibition activity (AChEI) of coumarin 3 were investigated, with the highest observed AChEI activity providing 48.25% inhibition. The electronic absorption and emission spectra revealed that 3 exists as two, main keto-enol tautomers. The ratios of these tautomers in both protic and aprotic solvents with different polarities and dielectric constants were calculated. The fluorescence of coumarin 3 was enhanced upon increasing the medium viscosity, which was due to the resultant molecular rigidity. This criterion was further investigated using DNA, whereby 3 showed enhanced fluorescence upon its uptake in DNA grooves and was therefore tested as a novel DNA fluorescent stain.

Glucosylceramide Plays a Role in Fungal Germination, Lipid Raft Organization and Biofilm Adhesion of the Pathogenic Fungus Scedosporium aurantiacum

Infections caused by Scedosporium species present a wide range of clinical manifestations, from superficial to disseminated, especially in immunocompromised patients. Glucosylceramides (GlcCer) are glycosphingolipids found on the fungal cell surface and play an important role in growth and pathogenicity processes in different fungi. The present study aimed to evaluate the structure of GlcCer and its role during growth in two S. aurantiacum isolates. Purified GlcCer from both isolates were obtained and its chemical structure identified by mass spectrometry. Using ELISA and immunofluorescence techniques it was observed that germination and NaOH-treatment of conidia favor GlcCer exposure. Monoclonal anti-GlcCer antibody reduced germination when cultivated with the inhibitor of melanin synthesis tricyclazole and also reduced germ tube length of conidia, both cultivated or not with tricyclazole. It was also demonstrated that anti-GlcCer altered lipid rafts organization, as shown by using the fluorescent stain filipin, but did not affect the susceptibility of the cell surface to damaging agents. Anti-GlcCer reduced total biomass and viability in biofilms formed on polystyrene plates. In the presence of anti-GlcCer, germinated S. aurantiacum conidia and biofilms could not adhere to polystyrene with the same efficacy as control cells. These results highlight the relevance of GlcCer in growth processes of S. aurantiacum.

Live cell fluorescent stain of bacterial curli and biofilm through supramolecular recognition between bromophenol blue and CsgA

A curli fluorescent light-up probe called bromophenol blue, which binds to curli via recognizing CsgA.

Highly selective staining and quantification of intracellular lipid droplets with a compact push–pull fluorophore based on benzothiadiazole

A robust lipophilic dye, based on the structures of the benzothiadiazole heterocycle, was shown to be a potent fluorescent stain for the selective imaging of lipid droplets (LDs) within both live and fixed human cells.

Comparison of Acid-Fast Stain and Auramine Rhodamine Fluorescent Smear on Bronchoalveolar Lavage Specimens Submitted for Cytologic Examination

Objectives Testing of bronchoalveolar lavage specimens with acid-fast bacilli (AFB) stain is not routinely performed in many institutions. In 2017, we began performing AFB stain on all BAL specimens submitted for cytologic examination. Herein, we evaluate the diagnostic value of this test in comparison to the auramine rhodamine fluorescent stain performed in parallel by the microbiology laboratory for specimens also submitted for AFB culture. Methods We retrospectively reviewed all BAL specimens that were reported as culture positive for Mycobacteria spp. (n = 109) by our microbiology laboratory between 7/20/2017 and 12/30/2018. Of these, 84 (77.0%) specimens were concurrently submitted for cytologic examination and reviewed by a board-certified cytopathologist. Results Of the 84 culture-positive BAL specimens submitted for cytologic exam, only 2 cases were positive for acid-fast bacilli on cytologic examination with AFB stain, yielding a sensitivity of 2.38%. In comparison, 11 of those specimens were identified on auramine rhodamine fluorescent stain, yielding a sensitivity of 13.1%. Both cases identified by the AFB stain on cytology were also identified by auramine rhodamine stain in microbiology. These data indicate that AFB stain conducted in cytology is 81.2% less sensitive for detection of AFB when compared to auramine rhodamine stain. All cases identified on smear and AFB stain (n = 11) belonged to the Mycobacterium avium-intracellulare complex. Conclusion Our study results suggest that in a low-prevalence population, the use of AFB stain on BAL specimens sent for cytologic examination lacks sensitivity and is unnecessary if the same specimen is also sent for microbiologic culture and auramine rhodamine stain. The use of AFB stain on BAL specimens that were not sent for AFB culture is suboptimal but may identify AFB in specimens obtained from patients for whom mycobacterial infection is not in the differential and may be clinically insignificant.

Selective Staining and Quantification of Intracellular Lipid Droplets with CBD-Fluor, a New and Versatile Push-Pull Fluorophore

A novel lipophilic dye, based on the structures of benzothiadiazole heterocycles, was shown to be an effective fluorescent stain for the imaging of lipid droplets (LDs) within both fixed and live cells. Its high photo stability, large Stokes shift, and improved staining and specificity over that of commercial dye Nile Red highlight its great potential as a versatile chemical tool for facilitating LD imaging and research.