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3.
Indian J Ophthalmol ; 68(3): 504-509, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32057013

RESUMEN

Purpose: To evaluate the accuracy of Spot photoscreener (PS) as a noncycloplegic photorefractor in detecting amblyopia risk factors (ARFs) in preschool children in an Indian eye clinic setting. Also, to derive appropriate cutoff values for screening to obtain maximum sensitivity and specificity of the device in detecting ARF. Methods: This was a cross-sectional study conducted in the outpatient pediatric eye clinic at a tertiary eye care institute. A Spot PS was used to screen all the children between the ages of 6 months and 5 years that presented to the eye clinic from August 2018 to October 2018. This screening was followed by a complete eye examination, including cycloplegic refraction by a masked examiner. The 2013 American Association for Pediatric Ophthalmology and Strabismus (AAPOS) guidelines were considered the standard cutoff values for clinically significant refractive error in children younger than 5 years of age. Results: The study comprised of 219 children. The Spot PS diagnosed 135 (61.64%) children with ARF as compared with 124 (56.62%) children detected by clinic examination. For ARF detection, the Spot photoscreeneer had 85.48% sensitivity, 69.47% specificity, 78.52% positive predictive value and 78.57% negative predictive value. The sensitivity for detection of strabismus and hypermetropia was very low (42% and 36%, respectively). The 95% limits of agreement ranged from -5.48 to +5.59 diopters (D) with a bias of 0.06 D for spherical equivalent between noncycloplegic photorefraction and cycloplegic refraction. Conclusion: The Spot PS may be used as a screening tool to detect ARF in children younger than 5 years of age keeping its limitations in consideration. However, the performance can be improved by modifying the cutoff values for the referral.


Asunto(s)
Ambliopía/diagnóstico , Refracción Ocular/fisiología , Medición de Riesgo/métodos , Selección Visual/instrumentación , Ambliopía/epidemiología , Ambliopía/fisiopatología , Preescolar , Estudios Transversales , Diseño de Equipo , Femenino , Humanos , India/epidemiología , Lactante , Masculino , Prevalencia , Derivación y Consulta , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Riesgo
4.
Bioresour Technol ; 268: 237-246, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30081283

RESUMEN

This study was conducted with the aim of embedding circular economies (waste recycling) with photosynthetic biorefineries, for production of commercially viable by-products. Since nitrogen source constitute the major input costs for commercial Arthrospira sp. production, the use of nitrogen rich wastewater for Arthrospira sp. cultivation could significantly reduce their production costs. This study evaluated the effects of high concentrations (8.5-120 mM) of alternative nitrogen sources (urea, ammonium and nitrite) on the biochemical, pigment and proteomic profile of Arthrospira sp., under batch and continuous conditions. Arthrospira sp. cells fed with urea were quantified with modified biochemical and proteomic profile compared to the nitrate fed cells. No inhibitory effect of urea was observed on the biomass even at 120 mM. Nitrite fed cells exhibited comparable biochemical and proteomic profiles as nitrate fed cells. These results clearly indicated at the possibility of using urea rich wastewater streams for profitable cultivation of Arthrospira sp.


Asunto(s)
Fotosíntesis , Proteómica , Spirulina , Aguas Residuales , Biomasa , Nitrógeno , Reciclaje
5.
Bioresour Technol ; 267: 492-501, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30041143

RESUMEN

The ability of cyanobacterium Arthrospira sp. to assimilate waste nitrogen sources (ammonium and urea) makes it an important candidate for wastewater management. The aim of this work was to evaluate a cultivation approach based on continuous-transitional-feeding regime (nitrate-ammonium-nitrate) in a photobioreactor to assess the effects of ammonium salts on Arthrospira sp. PCC 8005 metabolism. Using a comprehensive biochemical, proteomic and stoichiometric profiling of biomass, this study demonstrated that the proposed cultivation approach could increase the proteins and pigments yields by 20-30%, compared to the respective yields obtained from wild-type Arthrospira sp. strain A light-energy-transfer model was used to predict the biomass and oxygen productivities of Arthrospira sp. cultivated under transitional-feeding regime. 95 ±â€¯2% match was observed between the experimental and simulated productivities. This study thus opened new avenues for use of ammonium rich wastewater for commercial production of high value pigments, biofuel and bioplastics using Arthrospira sp.


Asunto(s)
Desnitrificación , Fotobiorreactores , Proteómica , Spirulina , Biomasa , Modelos Teóricos , Nitrógeno
6.
Retin Cases Brief Rep ; 12(4): 272-274, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28033226

RESUMEN

PURPOSE: To report optical coherence tomography-based videoimaging of alive subretinal cysticercus along with its mobile scolex. METHODS: Spectral-domain optical coherence tomography was used to record high-definition videoimages, using the inbuilt motion tracker, in a 12-year-old boy with history of neurocysticercosis. RESULT: The scolex was found to be sensitive to light, and contractile movements were seen in the cyst wall and the germinative layers. The patient underwent vitrectomy, and the diagnoses were confirmed with histopathologic assessment. CONCLUSION: Optical coherence tomography is a useful tool for diagnosing posterior segment cysticercosis. The intense motion of scolex does not impact the surrounding ocular structures.


Asunto(s)
Cisticercosis/diagnóstico por imagen , Cysticercus , Infecciones Parasitarias del Ojo/diagnóstico por imagen , Enfermedades de la Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Animales , Niño , Humanos , Masculino
7.
Bioresour Technol ; 237: 78-88, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28400171

RESUMEN

The aim of the present study was to evaluate the effects of varying concentrations of different nitrogen sources (individually or in combination) on the biochemical, transcriptomic and proteomic profiles of Arthrospira sp. PCC 8005 under batch and continuous modes. In batch mode, while ammonium showed a repressive effect on nitrate-assimilation pathway of the cyanobacteria; better growth and nutrient uptake rate were observed in presence of urea than nitrate. The inhibitory effect of ammonium was further confirmed by the continuous photobioreactor study wherein the nutrient feed was transiently replaced from nitrate to ammonium (28mM turbiostat regime). The changes in lipid, exopolysaccharide, transcriptomic and proteomic profiles of cyanobacteria on transition from nitrate to ammonium indicated at an onset of nutrient stress.


Asunto(s)
Cianobacterias , Regulación Bacteriana de la Expresión Génica , Nitrógeno , Proteómica , Spirulina , Nitratos
8.
Bioresour Technol ; 221: 576-587, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27689351

RESUMEN

The present study aimed to develop thermo-tolerant mutants of Chlorella pyrenoidosa NCIM 2738 for high lipids production. For this, ethyl methane sulfonate was used, which generated two effective thermo-tolerant mutants, M18 and M24 of Chlorella pyrenoidosa NCIM 2738, capable of surviving at temperature up to 47°C and showing improved lipid and biomass yields. They showed 59.62% and 50.75% increase, respectively in lipid content compared to wild type at 30°C, which could not grow at temperature above 35°C. The novelty of this study lied in incorporation of PAM Flurometry with mutagenesis to generate thermo-tolerant mutants of C. pyrenoidosa and investigating the reasons for increased yields of mutants at cellular and photosynthetic levels with the aim to use them for commercial biodiesel production.


Asunto(s)
Biotecnología/métodos , Chlorella/genética , Chlorella/metabolismo , Lípidos/biosíntesis , Biocombustibles , Biomasa , Chlorella/efectos de los fármacos , Metanosulfonato de Etilo/farmacología , Mutagénesis , Complejo de Proteína del Fotosistema II/metabolismo , Temperatura
9.
J Struct Biol ; 196(3): 385-393, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27592616

RESUMEN

In cyanobacteria, the nitrogen and carbon metabolisms are functionally bridged and consequently respond to the carbon-to-nitrogen ratio. Consequently, a nitrogen deficiency results in carbon excess. For the first time, the biological adaptation of Arthrospira sp. PCC 8005 to nitrogen starvation has been deeply characterized at the cellular structure scale. The results indicated that the carbon excess is rerouted into carbon storage granules, such as the polyhydroxyalkanoate and glycogen granules corroborating existing data. Additionally, this photosynthetic organism hugely secreted exopolysaccharides, which could constitute another biological carbon reservoir. It has been reported that few cells in trichomes of Arthrospira sp. PCC 8005 still display a high level of fluorescence after a long-term nitrogen starvation. The transmission electron microscopy showed that some cells still contained thylakoids and phycobilisomes after this long-term nitrogen starvation, which could explain the remaining fluorescence.


Asunto(s)
Proteínas Bacterianas/química , Carbono/química , Nitrógeno/química , Fotosíntesis , Proteínas Bacterianas/genética , Carbono/metabolismo , Regulación Bacteriana de la Expresión Génica , Nitrógeno/metabolismo , Spirulina/química , Spirulina/genética , Inanición
10.
Bioresour Technol ; 218: 934-43, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27450124

RESUMEN

The aim of the present work was to develop a mathematical model to describe the biomass and (total) lipid productivity of Chlorella pyrenoidosa NCIM 2738 under heterotrophic conditions. Biomass growth rate was predicted by Droop's cell quota model, while changes observed in cell quota (utilization) under carbon excess conditions were used for the modeling and predicting the lipid accumulation rate. The model was simulated under non-limiting (excess) carbon and limiting nitrate concentration and validated with experimental data for the culture grown in batch (flask) mode under different nitrate concentrations. The present model incorporated two modes (growth and stressed) for the prediction of endogenous lipid synthesis/induction and aimed to predict the effect and response of the microalgae under nutrient starvation (stressed) conditions. MATLAB and Genetic Algorithm were employed for the prediction and validation of the model parameters.


Asunto(s)
Biomasa , Chlorella/crecimiento & desarrollo , Modelos Teóricos , Procesos Heterotróficos , Cinética , Gotas Lipídicas/química , Microalgas/crecimiento & desarrollo
11.
Ethiop J Health Sci ; 24(2): 117-24, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24795512

RESUMEN

BACKGROUND: High prevalence rates of work-related musculoskeletal disorders (WRMSD) among dentists have been reported. Complementary and alternative medicine (CAM) therapies can be helpful in managing and preventing work-related musculoskeletal disorders. The purpose of this study was to determine if dental professionals are using CAM for work-related musculoskeletal disorders. Who have greater job satisfaction: dentist who uses Complementary and alternative medicine (CAM) or conventional therapy (CT) as a treatment modality for WRMSD. METHOD: Dentists who registered in Uttar Pradesh state, India under Indian Dental Council, Uttar Pradesh branch (n=1134) were surveyed. Data were analyzed using univariate and bivariate analyses and logistic regression. RESULT: A response rate of 53% (n=601) was obtained, revealing that 82% (n=487) of the respondents suffered from work-related musculoskeletal disorders. The use of complementary and alternative medicine or conventional therapy was reported among 80% (n=390) of the dentists with work-related musculoskeletal disorders. Complementary and alternative medicine users reported greater overall health compared to conventional therapy users (P<0.001). Of those with work-related musculoskeletal disorders, 35.5% (n=172) considered a career change for once, and 4.0% (n=19) reported having left dentistry. CONCLUSION: Complementary and alternative medicine therapies may improve quality of life, reduce work disruptions and enhance job satisfaction for dentists who suffer from work-related musculoskeletal disorders. It is important that dentists incorporate complementary and alternative medicine strategies into practice to facilitate musculoskeletal health that will enable longer and healthier careers, increase productivity, provide safer workplace and prevent musculoskeletal disorders.


Asunto(s)
Terapias Complementarias/estadística & datos numéricos , Odontólogos/estadística & datos numéricos , Satisfacción en el Trabajo , Enfermedades Musculoesqueléticas/terapia , Traumatismos Ocupacionales/terapia , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Musculoesqueléticas/psicología , Traumatismos Ocupacionales/epidemiología , Traumatismos Ocupacionales/psicología , Prevalencia , Adulto Joven
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