Biomimetic ion substituted and Co-substituted hydroxyapatite nanoparticle synthesis using Serratia Marcescens.

Biomimicry is becoming deep-rooted as part of bioceramics owing to its numerous functional advantages. Naturally occurring hydroxyapatite (HA) apart from primary nano structures are also characterised by various ionic substitutions. The ease of accommodating such key elements into the HA lattice is known to enhance bone healing properties of bioceramics. In this work, hydroxyapatite synthesized via biomimetic approach was substituted with individual as well as multiple cations for potential applications in bone repair. Ion substitutions of Sr, Mg and Zn was carried out on HA for the first time by using Serratia grown in a defined biomineralization medium. The individual ions of varying concentration substituted in Serratia HA (SHA) (Sr SHA, Mg SHA and Zn SHA) were analysed for crystallinity, functional groups, morphology and crystal size. All three showed decreased crystallinity, phase purity, large agglomerated aggregates and needle-shaped morphologies. Fourier transform infrared spectroscopy (FTIR) spectra indicated increased carbonate content of 5.8% resembling that of natural bone. Additionally, the reduced O-H intensities clearly portrayed disruption of HA lattice and subsequent ion-substitution. The novelty of this study lies primarily in investigating the co-substitution of a combination of 1% Sr, Zn and Mg in SHA and establishing the associated change in bone parameters. Scanning electron microscope (SEM) and transmission electron microscope (TEM) images clearly illustrated uniform nano-sized agglomerates of average dimensions of 20-50 nm length and 8-15 nm width for Sr SHA; 10-40 nm length and 8-10 nm width for both Zn SHA and Mg SHA and 40-70 nm length and 4-10 nm width in the case of 1% Sr, Zn, Mg SHA. In both individual as well as co-substitutions, significant peak shifts were not observed possibly due to the lower concentrations. However, cell volumes increased in both cases due to presence of Sr2+ validating its dominant integration into the SHA lattice. Rich trace ion deposition was presented by energy dispersive X-ray spectroscopy (EDS) and quantified using inductively coupled plasma optical emission spectrometer (ICP-OES). In vitro cytotoxicity studies in three cell lines viz. NIH/3T3 fibroblast cells, MG-63 osteosarcoma cells and RAW 264.7 macrophages showed more than 90% cell viability proving the biocompatible nature of 1% Sr, Zn and Mg in SHA. Microbial biomineralization by Serratia produced nanocrystals of HA that mimicked "bone-like apatite" as evidenced by pure phase, carbonated groups, reduced crystallinity, nano agglomerates, variations in cell parameters, rich ion deposition and non-toxic nature. Therefore ion-substituted and co-substituted biomineralized nano SHA appears to be a suitable candidate for applications in biomedicine addressing bone injuries and aiding regeneration as a result of its characteristics close to that of the human bone.

Pre-service Teachers Computational Thinking (CT) and Pedagogical Growth in a Micro-credential: A Mixed Methods Study.

Teacher preparation programs are essential to ensure pre-service teachers are equipped with the skills and knowledge necessary to teach in the PK-12 learning environment, but are rooted in a traditional paradigm of a compacted curriculum with little room for more content. The addition of Computational Thinking (CT) becomes one more thing to add to a packed schedule and integration of CT into established courses takes major redesign of courses. One university in Maryland, U.S. developed a CT focused micro-credential for K-8 pre-service and in-service teachers. In examining pre- and post-content surveys, reflection journal entries and lesson plans, pre-service teachers report CT and pedagogical content growth in their awareness and integration of CT in their lives and future classrooms. Results indicate a CT micro-credential could be an innovative solution to adding CT content to an over-packed, pre-service curriculum. In addition, CT micro-credential courses increased pre-service teachers' knowledge and self-awareness to the feasibility to proficiently implement CT across all courses.

Management of Cervical Tracheo-Esophageal Fistula by Lateral Cervical Approach: Our Experience'.

Acquired Tracheo-esophageal fistula (TEF) is a challenging and complicated condition. The laryngeal protection is lost in acquired TEF cases due to the established connection between the esophagus and the airways leading to aspiration, pneumonia, and acute respiratory distress syndrome. Malignancy contributes to about 80% of acquired TEF. Nonmalignant causes for TEF include prolonged ventilation, trauma (iatrogenic, penetrating, or blunt injury), foreign bodies, corrosive burns, and granulomatous infections. With the advancements in critical care, the incidence of TEF post-ventilation is on the rise in recent decades. We would like to share our experience managing ten cases of nonmalignant acquired cervical TEF by the lateral cervical approach at our institute. Apart from the isolated TEF cases, one patient with concomitant tracheal stenosis was repaired simultaneously with good postoperative results. TEF was identified in two cases following removal of T-tube and solid stent respectively and was repaired successfully with lateral cervical approach with strap muscle flap interposition.

Chlorella vulgaris cultivation in airlift photobioreactor with transparent draft tube: effect of hydrodynamics, light and carbon dioxide on biochemical profile particularly ω-6/ω-3 fatty acid ratio.

Chlorella vulgaris is used for food and feed applications due to its nutraceutical, antioxidant and anticancer properties. An airlift photobioreactor comprising transparent draft tube was used for C. vulgaris cultivation. The effect of reactor parameters like hydrodynamics (0.3-1.5 vvm), light intensity (85-400 µmol m-2 s-1), photoperiod (12-24 h) and gas-phase carbon dioxide (CO2) concentration (5-15% v/v) were evaluated on microalgae and associated bacterial growth, biochemical profile; with special emphasis on ω-3, ω-6 fatty acids, and vitamin B12. The optimal growth of C. vulgaris without CO2 supplementation was observed at 1.2 vvm, which was associated with higher algal productivity, chlorophyll, vitamin B12 content, and bacterial load along with 72% of nitrate removal. The higher light intensity (400 µmol m-2 s-1) and photoperiod (24:0) increased biomass productivity and ω-3 fatty acid content (in lipid) up to 2-3 fold. The elevated levels of gas-phase CO2 concentration (15% v/v) enhanced EPA content up to 7% and biomass productivity up to 171 mg L-1 day-1. However, the increase in CO2 concentration lowered vitamin B12 content (up to 30%) and bacterial load (2-3 log). Also, all the cultivation conditions favoured desirable ω-6/ω-3 ratio(in the range of 1-2).

Studies on expression levels of pil Q and fli P genes during bio-electrogenic process in Kluyvera georgiana MCC 3673.

The bacterium Kluyvera georgiana MCC 3673 transfers electrons directly to the electrode for bio-electricity generation in microbial fuel cell (MFC). This could be due to the formation of biofilm on the surface of electrode or with through the extracellular appendages, or both. The role of extracellular appendages pili and flagella in exo-electron transfer mechanism was investigated. The expression level of the genes fli P and pil Q for pili and flagella, respectively, in K. georgiana MCC 3673 was compared in MFC and in shake flask. The transcript analysis was done by qRT-PCR at different times and conditions. The expression level of pil Q transcript in K. georgiana MCC 3673 showed over twofold higher expression during bio-electrogenic process, compared to the one inoculated in shake flask. Similarly, fli P had also showed similar kind of expression in MFC compared to that in shake flask. Higher level of pil Q and fli P transcripts were observed throughout bio-electrogenic process. The level of pil Q was found to be nearly fourfold higher in biofilm-forming cells forming compared to the cells in suspension form. The obtained results suggest that flagella have a role in movement of bacterium towards electrode for donating the electron in absence of oxygen, and pili aiding in adhering on the surface of electrode and forming biofilm. The cumulative effect of fli P and pil Q resulted in exo-electron transfer to the electrode and bio-electricity generation process. The open circuit potential (OCV) of + 0.7 V was produced with the maximum power density of 393 ± 14 mW/m2 in MFC.

Cerebral venous sinus thrombosis as the initial presentation of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a hypercoagulable state due to a variety of mechanisms. Herein, we discuss the case of a 40-year-old gentleman who presented with cerebral venous sinus thrombosis (CVST) as the first manifestation of underlying SLE. On initial presentation, he did not endorse any other signs and symptoms to suggest the presence of an autoimmune condition. Work-up revealed an absence of antiphospholipid antibodies. Further evaluation uncovered the underlying etiology of the CVST as SLE-induced nephrotic syndrome. The existing literature on CVST suggests that there are only two other biopsy-proven cases of lupus nephritis leading to nephrotic range proteinuria as the etiology for CVST. Given the rarity of this presentation, there are no clearly delineated treatment strategies.

Laccase Immobilization Strategies for Application as a Cathode Catalyst in Microbial Fuel Cells for Azo Dye Decolourization.

Enzymatic biocathodes have the potential to replace platinum as an expensive catalyst for the oxygen reduction reaction in microbial fuel cells (MFCs). However, enzymes are fragile and prone to loss of activity with time. This could be circumvented by using suitable immobilization techniques to maintain the activity and increase longevity of the enzyme. In the present study, laccase from Trametes versicolor was immobilized using three different approaches, i.e., crosslinking with electropolymerized polyaniline (PANI), entrapment in copper alginate beads (Cu-Alg), and encapsulation in Nafion micelles (Nafion), in the absence of redox mediators. These laccase systems were employed in cathode chambers of MFCs for decolourization of Acid orange 7 (AO7) dye. The biocatalyst in the anode chamber was Shewanella oneidensis MR-1 in each case. The enzyme in the immobilized states was compared with freely suspended enzyme with respect to dye decolourization at the cathode, enzyme activity retention, power production, and reusability. PANI laccase showed the highest stability and activity, producing a power density of 38 ± 1.7 mW m-2 compared to 25.6 ± 2.1 mW m-2 for Nafion laccase, 14.7 ± 1.04 mW m-2 for Cu-Alg laccase, and 28 ± 0.98 mW m-2 for the freely suspended enzyme. There was 81% enzyme activity retained after 1 cycle (5 days) for PANI laccase compared to 69% for Nafion and 61.5% activity for Cu-alginate laccase and 23.8% activity retention for the freely suspended laccase compared to initial activity. The dye decolourization was highest for freely suspended enzyme with over 85% decolourization whereas for PANI it was 75.6%, Nafion 73%, and 81% Cu-alginate systems, respectively. All the immobilized laccase systems were reusable for two more cycles. The current study explores the potential of laccase immobilized biocathode for dye decolourization in a microbial fuel cell.

Suitable Alternative for Human Cadaver Temporal Bone Dissection: Comparative Micro Ear Anatomy of Cattle, Pig and Sheep with Human.

The study was undertaken to compare the micro ear anatomy of three commonly available animal models which are expected to have similar anatomy to human and to find out suitable model among them as an alternative for human cadaver temporal bone dissection. This is an observational study of comparison of micro ear anatomy of the three animal models with human. Decapitated heads of cattle, pig and sheep were collected from slaughter houses, soft tissues along with brain were removed and preserved in commercially available formalin preservative. CT scan was taken for the three specimens and 3D reconstructions were done. Each specimen was subjected to micro dissection and the anatomical features were studied and compared with human. Among the three animal models sheep is found to be an ideal model for a beginner because of ease of exposure of bone, very thin cortical bone, and no cellularity, good exposure of all the middle ear structures and similar interrelations of middle ear structures with human. Pig may not be an ideal model because of abundant fatty soft tissues, thick periosteum very narrow space occupied by the middle ear, difficulty in accessing cellularity small fragile ossicular chain and overhanging facial nerve.

Characterization of membrane vesicles secreted by seaweed associated bacterium Alteromonas macleodii KS62.

Recent studies have reported abundant presence of bacterial extracellular membrane vesicles in the marine environment. However, the ecological significance of these bacterial vesicles in the marine environment is only beginning to be explored. In present study, for the first time we report and characterize membrane vesicles secreted by a seaweed associated bacterium, Alteromonas macleodii KS62. Proteomics studies revealed that the vesicle proteome was rich in hydrolytic enzymes (30%) like glycoside hydrolases, proteases, sulphatases, lipases, nucleases and phosphatases. Zymography experiments and enzyme assays established that the vesicles carry active κ-carrageenan degrading enzymes. κ-carrageenan is a major polysaccharide of cell walls of certain red seaweeds like Kappaphycus. Purified membrane vesicles were successfully able to degrade Kappaphycus biomass. Based on these results, we discuss how the hydrolase-rich vesicles may play a role in red seaweed cell wall degradation so that the bacteria can invade and colonise the seaweed biomass establishing a saprophytic lifestyle. We also discuss the role of these vesicles in nutrient acquisition and their ecological significance in the marine environment.

Impact of Sputum Volume in the Diagnosis of Smear-Positive Pulmonary Tuberculosis.

OBJECTIVE: To find the impact of sputum volume in the diagnosis of smear-positive (SP) pulmonary tuberculosis (PT) and its association with gender. MATERIALS AND METHODS: The study was conducted in the Department of Microbiology, GSL Medical College. PT patients were included and informed to provide good-quality sputum; volume was not mentioned. Smears were stained by Ziehl-Neelsen technique. Based on the volume of sample submitted, the participants were divided into three groups. Chi-square test was used to find the statistical significance; P < 0.05 was considered statistically significant. RESULTS: Volume-wise, 22, 38, and 74 participants submitted sputum, respectively, in groups, <2 mL, 2-5 mL, and >5 mL; statistically, the difference was significant (P < 0.05). The smear positivity was 13% (15), 28% (32), and 59% (68), respectively, in groups, <2 mL, 2-5 mL, and >5 mL; statistically, the difference was significant (P < 0.05). Among the missed cases, the difference was statistically significant (P < 0.05) in males and the difference was statistically not significant (P > 0.05) in females. CONCLUSIONS: Notable number of SP cases are identified in ≤5 mL sputum. Hence, sample should not be discarded/rejected if the volume is <5 mL.

Xerogel based catalyst for improved cathode performance in microbial fuel cells.

In a microbial fuel cell (MFC) the reduction reaction at cathode has been a limiting factor in achieving maximum power density, and numerous strategies have been implemented in an attempt to overcome this. Herein, we demonstrate that carbon xerogel (CX) doped with iron (Fe) and nitrogen (N) followed by modification with graphene oxide (GO) is an efficient catalyst for MFCs. The CXFeNGO catalyst was characterized using a scanning electron microscope, and X-ray diffraction, and the catalytic activity was confirmed using cyclic voltammetry studies. At the anode, colonization of bacterial cells on the electrode surface, forming a biofilm, was observed. When the CXFeNGO-modified electrode was used at the cathode in the MFC, a maximum power density of 176.5 ± 6 mW m-2 was obtained, compared to that of plain graphite electrode, which produced 139.1 ± 4 mW m-2. The power density of the modified electrode is thus 26.8% higher. The power density further increased to 48.6% when the pH of the catholyte was increased to 12, producing a power density of 207 ± 4 mW m-2.

Thermal assisted alkaline pretreatment of rice husk for enhanced biomass deconstruction and enzymatic saccharification: Physico-chemical and structural characterization.

Thermal assisted alkaline pretreatment (TAAP) of rice husk (RH) was investigated to facilitate enzymatic saccharification by enhancing the enzyme accessibility to cellulosic components. Statistically guided experiments based on the Box-Behnken design involving four factors viz. biomass loading, particle size, NaOH loading and reaction time was considered for optimization. The maximum sugar yield of 371 mg g-1 biomass was obtained at optimized pretreatment condition [biomass loading (10% w/w), particle size (0.25-0.625 mm), NaOH loading (2% w/w), and reaction time (40 min)]. The TAAP of RH resulted in the efficient removal of lignin (14.9-54% (w/w)) with low hemicellulose solubilization [10.7-33.1% (w/w)] and with a simultaneous increase in cellulose concentration [32.65-51.65% (w/w)]. The SEM analysis indicated increased porosity and biomass disruption during TAAP. The FTIR analysis showed progressive removal of noncellulosic constituents, and XRD analysis revealed an increase in cellulose crystallinity post-TAAP indicating the effectiveness of pretreatment.

One-sample two-smear versus two-sample two-smear approach for the diagnosis of pulmonary tuberculosis.

BACKGROUND: To evaluate the efficacy of one-sputum sample two-smear approach for the diagnosis of pulmonary tuberculosis (PT). MATERIALS AND METHODS: Data from January 2012 to December 2015 were analyzed to find (1) number of smear positives (SPs) by spot (S) sample with one and two smears; (2) number of SPs by morning (M) sample with one and two smears; and (iii) number of SPs by two samples with two smears, that is, same-day (SS2) and spot morning (SM) approaches. The Chi-square test was used to evaluate the statistical difference in SP cases. RESULTS: With one-sample two-smear approach, the smear positivity (SPT) was 87% and 87.5%, for S and M samples, respectively, for Ziehl-Neelsen (ZN) staining; whereas, SPT was 96% and 97%, respectively, for S and M samples, for fluorescent staining (FS) technique. With two-sample two-smear approach, for ZN staining, SPT was 89% each and for FS technique, SPT was 97% and 99%, respectively, for SS2 and SM approaches. The difference was not statistically significant (P > 0.05) between one- and two-sample approaches in the staining techniques. CONCLUSION: Significant number of SP cases are identified by S sample two-smear approach. Thus, the World Health Organization/Revised National Tuberculosis Control Programme can initiate S sample two-smear approach for the diagnosis of PT.

Growth and biochemical characteristics of an indigenous freshwater microalga, Scenedesmus obtusus, cultivated in an airlift photobioreactor: effect of reactor hydrodynamics, light intensity, and photoperiod.

The freshwater green algae, Scenedesmus obtusus, was cultivated in a 3.4 L airlift photobioreactor. The hydrodynamic parameters were estimated at different inlet gas flow rates (1, 2, 3, and 4 LPM) and their subsequent impact on the growth and biochemical characteristics of microalgae was studied. The biomass concentration and productivity increased with an increase in flow rates from 1 to 4 LPM. A maximum of 0.07 g L-1 day-1 productivity of biomass was attained at 3 LPM. An increase of total carbohydrate content from 19.6 to 26.4% was noticed with increment in the inlet flow rate of gas from 1 to 4 LPM. Major variations in total fatty acid content were not observed. The impact of light irradiance on growth and biochemical characteristics of S. obtusus was also evaluated. A maximum biomass productivity of 0.103 g L-1 day-1 was attained at an illumination of 150 µmol m-2 s-1 under continuous light. The major fatty acids reported were palmitic acid (C16:0), α-linolenic acid (C18:3), linoleic acid (C18:2), and oleic acid (C18:1). Biodiesel properties of the microalgae were estimated under various culture conditions. The light profile inside the airlift reactor was experimentally measured and the predictive modelling of light profile was also attempted.

Capillary flow-driven microfluidic device with wettability gradient and sedimentation effects for blood plasma separation.

We report a capillary flow-driven microfluidic device for blood-plasma separation that comprises a cylindrical well between a pair of bottom and top channels. Exposure of the well to oxygen-plasma creates wettability gradient on its inner surface with its ends hydrophilic and middle portion hydrophobic. Due to capillary action, sample blood self-infuses into bottom channel and rises up the well. Separation of plasma occurs at the hydrophobic patch due to formation of a 'self-built-in filter' and sedimentation. Capillary velocity is predicted using a model and validated using experimental data. Sedimentation of RBCs is explained using modified Steinour's model and correlation between settling velocity and liquid concentration is found. Variation of contact angle on inner surface of the well is characterized and effects of well diameter and height and dilution ratio on plasma separation rate are investigated. With a well of 1.0 mm diameter and 4.0 mm height, 2.0 µl of plasma was obtained (from <10 µl whole blood) in 15 min with a purification efficiency of 99.9%. Detection of glucose was demonstrated with the plasma obtained. Wetting property of channels was maintained by storing in DI water under vacuum and performance of the device was found to be unaffected over three weeks.

Decolourisation of Acid orange 7 in a microbial fuel cell with a laccase-based biocathode: Influence of mitigating pH changes in the cathode chamber.

Biocathodes may be a suitable replacement of platinum in microbial fuel cells (MFCs) if the cost of MFCs is to be reduced. However, the use of enzymes as bio-cathodes is fraught with loss of activity as time progresses. A possible cause of this loss in activity might be pH increase in the cathode as pH gradients in MFCs are well known. This pH increase is however, accompanied by simultaneous increase in salinity; therefore salinity may be a confounding variable. This study investigated various ways of mitigating pH changes in the cathode of MFCs and their effect on laccase activity and decolourisation of a model azo dye Acid orange 7 in the anode chamber. Experiments were run with catholyte pH automatically controlled via feedback control or by using acetate buffers (pH 4.5) of various strength (100mM and 200mM), with CMI7000 as the cation exchange membrane. A comparison was also made between use of CMI7000 and Nafion 117 as the transport properties of cations for both membranes (hence their potential effects on pH changes in the cathode) are different. Results show that using Nafion 117 membrane limits salinity and pH changes in the cathode (100mM acetate buffer as catholyte) leading to prolonged laccase activity and faster AO7 decolourisation compared to using CMI7000 as a membrane; similarly automatic pH control in the cathode chamber was found to be better than using 200mM acetate buffer. It is suggested that while pH control in the cathode chamber is important, it does not guarantee sustained laccase activity; as salinity increases affect the activity and it could be mitigated using a cation selective membrane.

Capillary flow of blood in a microchannel with differential wetting for blood plasma separation and on-chip glucose detection.

We report capillary flow of blood in a microchannel with differential wetting for the separation of a plasma from sample blood and subsequent on-chip detection of glucose present in a plasma. A rectangular polydimethylsiloxane microchannel with hydrophilic walls (on three sides) achieved by using oxygen plasma exposure enables capillary flow of blood introduced at the device inlet through the microchannel. A hydrophobic region (on all four sides) in the microchannel impedes the flow of sample blood, and the accumulated blood cells at the region form a filter to facilitate the separation of a plasma. The modified wetting property of the walls and hence the device performance could be retained for a few weeks by covering the channels with deionised water. The effects of the channel cross-section, exposure time, waiting time, and location and length of the hydrophobic region on the volume of the collected plasma are studied. Using a channel cross-section of 1000 × 400 µm, an exposure time of 2 min, a waiting time of 10 min, and a hydrophobic region of width 1.0 cm located at 10 mm from the device inlet, 450 nl of plasma was obtained within 15 min. The performance of the device was found to be unaffected (provides 450 nl of plasma in 15 min) even after 15 days. The purification efficiency and plasma recovery of the device were measured and found to be comparable with that obtained using the conventional centrifugation process. Detection of glucose at different concentrations in whole blood of normal and diabetic patients was performed (using 5 µl of sample blood within 15 min) to demonstrate the compatibility of the device with integrated detection modules.

Removal of nutrients and organic pollution load from pulp and paper mill effluent by microalgae in outdoor open pond.

A mixed culture of microalgae, containing two Scenedesmus species, was analysed to determine its potential in coupling of pulp and paper mill effluent treatment and microalgal cultivation. Laboratory studies suggested that 60% concentration of wastewater was optimum for microalgal cultivation. A maximum of 82% and 75% removal of BOD and COD respectively was achieved with microalgal cultivation in outdoor open pond. By the end of the cultivation period, 65% removal of NO3-N and 71.29% removal of PO4-P was observed. The fatty acid composition of mixed microalgal culture cultivated with effluent showed the palmitic acid, oleic acid, linoleic acid and α-linolenic acid as major fatty acids. The results obtained suggest that pulp and paper mill effluent could be used effectively for cultivation of microalgae to minimise the freshwater and nutrient requirements.

Evaluation of indigenous fresh water microalga Scenedesmus obtusus for feed and fuel applications: Effect of carbon dioxide, light and nutrient sources on growth and biochemical characteristics.

Scenedesmus obtusus, a freshwater microalga, was evaluated for its growth and biochemical characteristics under various culture conditions. S. obtusus was tolerant at all tested CO2 concentrations up to 20%. Among the different nitrogen sources, urea showed enhanced biomass productivities up to 2-fold compared to control, where the nitrogen source was sodium nitrate. Light intensity and photoperiod had a significant effect on growth rate and biomass productivity. The growth rate was observed maximum under continuous light exposure at the light intensities, 30µmolm(-2)sec(-1) and 60µmolm(-2)sec(-1) The species was able to tolerate the salinity levels up to 25mM NaCl, where, the increase in the concentration of NaCl suppressed the growth. Ammonium acetate and glycine showed better growth rate and biomass productivity indicating mixotrophic ability of S. obtusus. Supplementation of acetate and bicarbonate significantly enhanced the biomass productivity. Biodiesel properties of S. obtusus cultivated at various culture conditions were estimated.

Same-day sputum smear microscopy for the diagnosis of pulmonary tuberculosis: direct vs. concentrated smear.

OBJECTIVE: To evaluate the efficacy of sputum microscopy by the concentration method using spot and morning and same-day smears for the diagnosis of pulmonary tuberculosis. METHODS: Three sputum specimens (spot, second spot and morning) were collected from study participants. Three smears were prepared from the direct sample and three using the N-acetyl-l-cysteine-sodium hydroxide concentration method. The smears were stained using Ziehl-Neelsen (ZN) staining, modified ZN (MZN) staining and fluorescent staining (FS). Smear results were pooled and compared in two categories: standard spot and morning, and same-day smears. The χ(2) test was used to evaluate the statistical difference in smear-positive cases. RESULTS: Among 3186 participants included in the study, smear positivity was respectively 9.6%, 9.8% and 10.8% for ZN, MZN and FS smears using spot and morning smears. Using same-day smears, smear positivity was respectively 9.5%, 9.8% and 10.6% for ZN, MZN and FS smears. Smear positivity increased to 16% with the concentration method. CONCLUSION: Nil dropouts and patient convenience are the added advantages of using same-day smears, and the concentration method improved smear positivity. Given these advantages, using same-day smears with the concentration method should be considered by the World Health Organization and India's Revised National Tuberculosis Control Programme.