Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
J Fluoresc ; 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38381236

RESUMEN

Deoxyribonucleic acid (DNA) capped silver nanoparticles are exceptional nanomaterials, featuring precise size and shape control enabled by DNA as a capping agent. DNA stabilizes these nanoparticles' role leading to uniform structures for diverse applications. These nanoparticles are excellent in photonics and medical applications, enhancing fluorescence and medical imaging. In this study, we explore the multifaceted applications of DNA-capped silver nanoparticles, delving into their optical, photocatalytic, antibacterial, cytotoxic, and bioimaging properties. Employing UV-visible absorption spectroscopy and scanning electron microscopy, we provide an analysis of confirmation of silver nanoparticles. The investigation demonstrates substantial photocatalytic efficacy, photodegradation of methylene blue is higher than rhodamine 6G. The presence of silver nanoparticles enhances the fluorescence of rhodamine 6G doped sol-gel glasses. Furthermore, our findings illustrate significant antibacterial effects, encompassing both Gram-positive and Gram-negative bacteria, with DNA-capped silver nanoparticles exhibiting antibacterial activity. Cytotoxicity assessments on HeLa cells reveal concentration-dependent effects, with an LC50 value of 47 µL. Additionally, the in vitro experiments with HeLa cells suggest the promising utility of DNA-capped silver nanoparticles for bioimaging applications. This comprehensive analysis highlights the multifunctionality and potential of DNA-capped silver nanoparticles, offering promising avenues for further exploration and innovation within various scientific domains, particularly in the realm of nanomaterial research.

2.
J Fluoresc ; 34(1): 437-448, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37284964

RESUMEN

Synthesizing nanoparticles in biotemplates has been cited as one of the most promising way to obtain monodispersed inorganic nanoparticles. In this method, uniform voids in porous materials serve as hosts to confine the synthesized nanoparticles. DNA template can be described as a smart glue for assembling nanoscale building blocks. Here we investigate the photocatalytic, antibacterial, cytotoxic, and bioimaging applications of DNA capped CdS. XRD, SEM, TEM, UV-visible absorption, and photoluminescence spectra were used to study structural, morphological, and optical properties of CdS nanoparticles. Prepared CdS nanoparticles exhibit visible fluorescence. The photocatalytic activity of CdS towards Rhodamine 6G and Methylene blue are 64% and 91% respectively. A disc-diffusion method is used to demonstrate antibacterial screening. It was shown that CdS nanoparticles inhibit Gram-positive bacteria and Gram-negative bacteria effectively. DNA capped CdS shows higher activity than uncapped CdS nanoparticles. MTT cell viability assays were carried out in HeLa cells to investigate the cytotoxicity for 24 h. At a concentration 2.5 µg/ml, it shows 84% cell viability and 43% viability at 12.5 µg/ml. The calculated LC50 value is equal to 8 µg/ml. These DNA capped CdS nanoparticles were taken for an in-vitro experiment with HeLa cells to exhibit the possibility of bioimaging applications. The present study suggests that the synthesized CdS nanoparticles could be a potential photocatalyst, antibacterial agent, and biocompatible nanoparticle for bioimaging applications.


Asunto(s)
Nanopartículas , Humanos , Células HeLa , Nanopartículas/química , Antibacterianos/química , Colorantes , ADN
3.
Paediatr Anaesth ; 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39212292

RESUMEN

INTRODUCTION: This quality improvement initiative is a continued pursuit to optimize outcomes by iteratively improving our opioid sparing anesthesia protocol for tonsillectomy with or without adenoidectomy at our pediatric ambulatory surgical center through data driven Plan-Do-Study-Act cycles. METHODS: From 1/2015 through 12/2023, our standardized tonsillectomy protocol underwent nine procedure-specific perioperative Plan-Do-Study-Act cycles, three procedure-specific postoperative prescription Plan-Do-Study-Act cycles, and four general ambulatory surgical center enhanced recovery Plan-Do-Study-Act cycles. We analyzed data from the medical record using statistical process control charts. The primary outcome measure was the percent of patients requiring intravenous opioid in the post anesthesia care unit. Secondary outcomes included maximum post anesthesia care unit pain score, the percent of patients requiring treatment for nausea and/or vomiting in the post anesthesia care unit, and the number of postoperative opioid prescription dosages. Balancing measures were average post anesthesia care unit length of stay, percent of patients with prolonged Post Anesthesia Care Unit length of stay (>120 min), and 30-day reoperation rate. RESULTS: A total of 5654 tonsillectomy with or without adenoidectomy cases were performed at our ambulatory surgical center from 2015 to 2023. The incidence of intravenous opioid administered in the post anesthesia care unit initially rose with opioid free anesthesia launch, but subsequently decreased below the target of 10%. Maximum post anesthesia care unit pain scores rose from mean 3.6 to 4.5, but subsequently returned to the baseline of 3.5, while the incidence of postoperative nausea and/or vomiting improved. The average post anesthesia care unit length of stay increased by 10 min with opioid free anesthesia; however, prolonged post anesthesia care unit stay and 30-day reoperation rates were unchanged. CONCLUSIONS: The continued refinement of our opioid sparing anesthesia protocol has led to reduced perioperative and home opioid use, stable maximum post anesthesia care unit pain scores, and improved postoperative nausea and vomiting rates, with only a slight increase in mean post anesthesia care unit length of stay.

4.
J Fluoresc ; 33(5): 1927-1940, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36913162

RESUMEN

In the present work, biocompatible CdS nanoparticles were synthesized using Schiff base ligand, 3-((2-(-(1-(2hydroxyphenyl)ethylidene)amino)ethyl)imino)-2-pentone, by a simple ultrasonic irradiation method. The structural, morphological, and optical properties were studied using XRD, SEM, TEM, UV-visible absorption, and photoluminescence (PL) spectra. The quantum confinement effect of the Schiff base capped CdS nanoparticles was confirmed by using UV-visible and PL spectrum analysis. This CdS nanoparticles were an effective photocatalyst for degrading rhodamine 6G and methylene blue with a 70% and 98% degradation capacity, respectively. Furthermore, the disc-diffusion method demonstrated that CdS nanoparticles inhibit G-positive bacteria and G-negative bacteria more effectively. These Schiff base capped CdS nanoparticles were taken for an in-vitro experiment with HeLa cells to exhibit the possibility of providing optical probes in biological applications and observed under a fluorescence microscope. In addition, MTT cell viability assays were carried out to investigate the cytotoxicity for 24 h. As a result of this study, 2.5 µg/ml doses of CdS nanoparticles are suitable for imaging and are effective in destroying HeLa cells. The present study suggests that the synthesized Schiff base capped CdS nanoparticles could be a potential photocatalyst, antibacterial agent, and biocompatible nanoparticle for bioimaging applications.


Asunto(s)
Nanopartículas , Bases de Schiff , Humanos , Células HeLa , Bases de Schiff/farmacología , Nanopartículas/química , Análisis Espectral , Diagnóstico por Imagen
5.
Paediatr Anaesth ; 29(7): 682-689, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31077491

RESUMEN

Pain management following pediatric tonsillectomy and adenotonsillectomy surgery is challenging and traditionally involves perioperative opioids. However, the recent national opioid shortage compelled anesthesiologists at Bellevue Surgery Center to identify an alternative perioperative analgesic regimen that minimizes opioids yet provides effective pain relief. We assembled an interdisciplinary quality improvement team to trial a series of analgesic protocols using the Plan-Do-Study-Act cycle. Initially, we replaced intraoperative morphine and acetaminophen (M/A protocol) with intraoperative dexmedetomidine and preoperative ibuprofen (D/I protocol). However, when results were not favorable, we rapidly transitioned to intraoperative ketorolac and dexmedetomidine (D/K protocol). The following measures were evaluated using statistical process control chart methodology and interpreted using Shewhart's theory of variation: maximum pain score in the postanesthesia care unit, postoperative morphine rescue rate, postanesthesia care unit length of stay, total anesthesia time, postoperative nausea and vomiting rescue rate, and reoperation rate within 30 days of surgery. There were 333 patients in the M/A protocol, 211 patients in the D/I protocol, and 196 patients in the D/K protocol. With the D/I protocol, there were small increases in maximum pain score and postanesthesia care unit length of stay, but no difference in morphine rescue rate or total anesthesia time compared to the M/A protocol. With the D/K protocol, postoperative pain control and postanesthesia care unit length of stay were similar compared to the M/A protocol. Both the D/I and D/K protocols had reduced nausea and vomiting rescue rates. Reoperation rates were similar between groups. In summary, we identified an intraoperative anesthesia protocol for pediatric tonsillectomy and adenotonsillectomy surgery utilizing dexmedetomidine and ketorolac that provides effective analgesia without increasing recovery times or reoperation rates.


Asunto(s)
Adenoidectomía/normas , Analgésicos no Narcóticos/uso terapéutico , Analgésicos Opioides/uso terapéutico , Manejo del Dolor/normas , Dolor Postoperatorio/tratamiento farmacológico , Tonsilectomía/normas , Adolescente , Niño , Preescolar , Dexmedetomidina/uso terapéutico , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Dimensión del Dolor , Mejoramiento de la Calidad
6.
Photochem Photobiol Sci ; 16(6): 870-882, 2017 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-28379273

RESUMEN

Laser-induced crystallization is emerging as a promising technique to crystallize biomolecules like amino acids and proteins. The use of external materials as nucleants and novel seeding methods open new paths for protein crystallization. We report here the results of experiments that explore the effect of nucleants on laser-based crystallization of microlitre droplets of small molecules, amino acids, and proteins. The role of parameters like solute concentration, droplet volume, type and size of the nucleant, and laser power, are systematically investigated. In addition to crystallization of standard molecules like NaCl, KCl, and glycine, we demonstrate the crystallization of negatively (l-histidine), and positively (l-aspartic acid) charged amino acids and lysozyme protein. Single crystal X-ray diffraction and Raman spectroscopy studies unequivocally indicate that the nucleants do not alter the molecular structure of glycine, hydrogen bonding patterns, and packing. Localized vaporization of the solvent near the nucleant due to photothermal heating has enabled us to achieve rapid crystallization - within 3 s - at laser intensities of 0.1 MW cm-2, significantly lower than those reported earlier, with both saturated and unsaturated solutions. The outcome of the current experiments may be of utility in tackling various crystallization problems during the formation of crystals large enough to perform X-ray crystallography.

7.
Bioorg Med Chem Lett ; 27(23): 5284-5290, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-29074256

RESUMEN

A series of 3-Benzylchroman-4-ones were synthesized and screened for anticancer activity by MTT assay. The compounds were evaluated against two cancerous cell lines BT549 (human breast carcinoma), HeLa (human cervical carcinoma), and one noncancerous cell line vero (normal kidney epithelial cells). 3b was found to be the most active molecule against BT549 cells (IC50 = 20.1 µM) and 3h against HeLa cells (IC50 = 20.45 µM). 3b also exhibited moderate activity against HeLa cells (IC50 = 42.8 µM). The molecular structures of 3h and 3i were solved by single crystal X-ray crystallographic technique. Additionally, the molecular docking studies between the tumour suppressor protein p53 with the lead compound 3h, which exhibited better anticancer activity against HeLa cells was examined.


Asunto(s)
Antineoplásicos/farmacología , Simulación del Acoplamiento Molecular , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Chlorocebus aethiops , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Relación Estructura-Actividad , Células Vero
8.
CNS Neurol Disord Drug Targets ; 22(6): 801-816, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35546747

RESUMEN

Parkinson's Disease (PD), known as Parkinsonism, is a neurodegenerative disease that mainly affects the elderly and is characterized by an extensive and progressive loss of dopaminergic neurons in the Substantia Nigra pars compacta (SNpc). Owing to genetic, environmental, and lifestyle changes, the incidence of PD has recently risen among adults. The most widely used PD treatment strategies include the use of dopamine agonists, anticholinergics, and enzyme inhibitors. The aquatic flora and fauna have become the emerging source of novel, structurally diverse bioactive compounds and, at present, the researchers concentrate their efforts on isolating, characterizing, and identifying many secondary metabolites of different nature to treat various disorders, including, neuroprotective marine natural products (MNPs). The bioactive peptides, tannins, carotenoids, alkaloids, polyunsaturated fatty acids (PUFA), and sulfated polysaccharides from the MNP's and their synthetic derivatives have demonstrated important neuroprotective activity in preclinical studies through multiple mechanisms. An extensive literature survey was carried out, and published articles from PubMed, Scifinder, Google Scholar, Web of Science, and Scopus were carefully reviewed to compile information on the MNPs to treat PD. This current review focus on neuroprotective MNPs and their probable biological pathways to treat PD based on their structure and bioactivities reported from 1990 to 2020.


Asunto(s)
Enfermedades Neurodegenerativas , Fármacos Neuroprotectores , Enfermedad de Parkinson , Trastornos Parkinsonianos , Humanos , Anciano , Enfermedad de Parkinson/metabolismo , Enfermedades Neurodegenerativas/tratamiento farmacológico , Trastornos Parkinsonianos/tratamiento farmacológico , Neuronas Dopaminérgicas/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Fármacos Neuroprotectores/farmacología
9.
Brain Res ; 1174: 76-91, 2007 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-17854780

RESUMEN

Our previous studies demonstrated that only a few days of housing in an enriched environment increases response strength and paired-pulse depression in the auditory cortex of awake and anesthetized rats [Engineer, N.D., Percaccio, C.R., Pandya, P.K., Moucha, R., Rathbun, D.L., Kilgard, M.P., 2004. Environmental enrichment improves response strength, threshold, selectivity, and latency of auditory cortex neurons. J Neurophysiol. 92, 73-82 and Percaccio, C.R., Engineer, N.D., Pruette, A.L., Pandya, P.K., Moucha, R., Rathbun, D.L., Kilgard, M.P., 2005. Environmental enrichment increases paired-pulse depression in rat auditory cortex. J Neurophysiol. 94, 3590-3600]. Multiple environmental and neurochemical factors likely contribute to the expression of this plasticity. In the current study, we examined the contribution of social stimulation, exercise, auditory exposure, and cholinergic modulation to enrichment-induced plasticity. We recorded epidural evoked potentials from awake rats in response to tone pairs and noise bursts. Auditory evoked responses were not altered by social stimulation or exercise. Rats that could hear the enriched environment, but not interact with it, exhibited enhanced responses to tones and increased paired-pulse depression. The degree to which enrichment increased response strength and forward masking was not reduced after a ventricular injection of 192 IgG-saporin. These results indicate that rich auditory experience stimulates physiological plasticity in the auditory cortex, despite persistent deficits in cholinergic activity. This conclusion may be beneficial to clinical populations with sensory gating and cholinergic abnormalities, including individuals with autism, schizophrenia, and Alzheimer's disease.


Asunto(s)
Corteza Auditiva/fisiología , Planificación Ambiental , Ambiente , Plasticidad Neuronal/fisiología , Acetilcolina/fisiología , Estimulación Acústica , Animales , Electrodos Implantados , Femenino , Condicionamiento Físico Animal , Ratas , Ratas Sprague-Dawley , Conducta Social
11.
J Oral Maxillofac Pathol ; 18(2): 299-302, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-25328317

RESUMEN

Malignant tumors of submandibular salivary gland are rare in occurrence. Squamous cell carcinoma of salivary glands accounts for about 0.9-4.7% of all salivary gland tumors with a predilection to occur in parotid gland due to perinodal involvement. Primary squamous cell carcinoma of submandibular salivary gland accounts to about 2% of the tumors and hence it is being represented for its rarity.

12.
Indian J Occup Environ Med ; 18(3): 122-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25598617

RESUMEN

BACKGROUND: Iron is the world's most commonly used metal and can usually be found with other elements in the form of steel. In this era of machines, it is the inevitable part in production of various materials like eyeglass frames, jet aircraft, the space shuttle, automobiles, and surgical instruments. Occupational factors make an important contribution to the global burden of disease, but the reliable data on occupational disease are much more difficult to obtain. Hence, the current study was carried out to find out the morbidity pattern among iron and steel workers. MATERIALS AND METHODS: A cross-sectional study. was carried out after obtaining permission from Institutional Ethics Committee in an iron and steel factory. Worker's detailed information regarding profile was taken in pretested questionnaire format after obtaining the informed written consent and explaining the purpose of study. Workers were also interviewed regarding their years of job, job satisfaction, usage of protective devices, and history of injuries during work. Worker's detailed general and systemic examination was conducted. RESULTS: The overall prevalence of morbidities among the workers was 60%. It was observed that commonest morbidity in the workers was lumbago (musculoskeletal pain), that is, 33.25%which was more in Group B (49.73%) than Group A (18.78%), followed by occupational dermatitis (27%) which more common in Group A (33.33%) than Group B (19.79%). It was seen that occupation-related morbidities were more prevalent in Group A, i.e. Exposed group (P < 0.001). CONCLUSION: It was observed that occupation-related morbidities were more common in exposed group (EG) than that of nonexposed group (NEG) and the difference was found to be statistically significant (P < 0.001).

13.
Am J Physiol Heart Circ Physiol ; 296(2): H237-46, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19028797

RESUMEN

Growing evidence indicates that nitrite, NO2-, serves as a circulating reservoir of nitric oxide (NO) bioactivity that is activated during physiological and pathological hypoxia. One of the intravascular mechanisms for nitrite conversion to NO is a chemical nitrite reductase activity of deoxyhemoglobin. The rate of NO production from this reaction is increased when hemoglobin is in the R conformation. Because the mammalian fetus exists in a low-oxygen environment compared with the adult and is exposed to episodes of severe ischemia during the normal birthing process, and because fetal hemoglobin assumes the R conformation more readily than adult hemoglobin, we hypothesized that nitrite reduction to NO may be enhanced in the fetal circulation. We found that the reaction was faster for fetal than maternal hemoglobin or blood and that the reactions were fastest at 50-80% oxygen saturation, consistent with an R-state catalysis that is predominant for fetal hemoglobin. Nitrite concentrations were similar in blood taken from chronically instrumented normoxic ewes and their fetuses but were elevated in response to chronic hypoxia. The findings suggest an augmented nitrite reductase activity of fetal hemoglobin and that the production of nitrite may participate in the regulation of vascular NO homeostasis in the fetus.


Asunto(s)
Sangre Fetal/enzimología , Hemoglobinas/metabolismo , Óxido Nítrico/sangre , Nitrito Reductasas/sangre , Nitritos/sangre , Animales , Biocatálisis , Enfermedad Crónica , Modelos Animales de Enfermedad , Ditionita/química , Femenino , Hipoxia Fetal/enzimología , Hemoglobinas/química , Concentración de Iones de Hidrógeno , Hipoxia/enzimología , Cinética , Metahemoglobina/metabolismo , Oxígeno/sangre , Embarazo , Conformación Proteica , Ovinos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA