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1.
Indian J Ophthalmol ; 71(5): 1783-1796, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37203031

RESUMEN

Diabetic macular edema (DME) is an important cause of visual impairment in the working-age group. Deep learning methods have been developed to detect DME from two-dimensional retinal images and also from optical coherence tomography (OCT) images. The performances of these algorithms vary and often create doubt regarding their clinical utility. In resource-constrained health-care systems, these algorithms may play an important role in determining referral and treatment. The survey provides a diversified overview of macular edema detection methods, including cutting-edge research, with the objective of providing pertinent information to research groups, health-care professionals, and diabetic patients about the applications of deep learning in retinal image detection and classification process. Electronic databases such as PubMed, IEEE Explore, BioMed, and Google Scholar were searched from inception to March 31, 2022, and the reference lists of published papers were also searched. The study followed the preferred reporting items for systematic review and meta-analysis (PRISMA) reporting guidelines. Examination of various deep learning models and their exhibition regarding precision, epochs, their capacity to detect anomalies for less training data, concepts, and challenges that go deep into the applications were analyzed. A total of 53 studies were included that evaluated the performance of deep learning models in a total of 1,414,169°CT volumes, B-scans, patients, and 472,328 fundus images. The overall area under the receiver operating characteristic curve (AUROC) was 0.9727. The overall sensitivity for detecting DME using OCT images was 96% (95% confidence interval [CI]: 0.94-0.98). The overall sensitivity for detecting DME using fundus images was 94% (95% CI: 0.90-0.96).


Asunto(s)
Aprendizaje Profundo , Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Humanos , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/complicaciones , Edema Macular/diagnóstico , Edema Macular/etiología , Tomografía de Coherencia Óptica/métodos , Fondo de Ojo
2.
J Mech Behav Biomed Mater ; 115: 104266, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33373960

RESUMEN

In this study, we employed Pectin (PC) as a matrix that is hybridized with three different nucleobase (NB) units (cytosine, thymine, uracil) to generate pectin-nucleobase(PC-NB) biocomposite films stabilized through bio-multiple hydrogen bonds (BMHBs) as drug carrier for anticancer 5-Fluorouracil (5-FU). Prepared biocomposite films were characterized by Fourier Transform Infra-red Spectroscopy (FTIR), X-ray Diffraction (XRD), Thermogravimmetry Analysis (TGA) and Scanning Electron Microscope (SEM). Mechanical and sorption properties were also evaluated. In vitro drug release performed in both acidic pH 1.2 (stomach pH) and alkaline pH 7.4 (intestinal pH) showed that incorporation of nucleobases into pectin significantly restricted release rate of 5-FU particularly under acidic condition (pH 1.2). Hemolysis assays demonstrated that PC-NB-5-FU biocomposite film drug carriers were hemocompatible. Confocal microscope analysis indicates facilitated cellular uptake of PC-NB-5-FU film in HT-29 colon cancer cell line, which in turn result in a higher potential of apoptosis. Confocal imaging of fluorescent live/dead cell indicators and MTT assay outcomes, both demonstrated significant decreases in cellular viability of PC-NB-5-FU biocomposite films. Collectively, our findings indicate that this PC-NB-5-FU biocomposite films can be conferred as a proficient formulation for targeted delivery of colon cancer drugs.


Asunto(s)
Neoplasias del Colon , Fluorouracilo , Neoplasias del Colon/tratamiento farmacológico , Preparaciones de Acción Retardada , Portadores de Fármacos , Liberación de Fármacos , Humanos , Espectroscopía Infrarroja por Transformada de Fourier
3.
Technol Health Care ; 29(3): 489-498, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32804106

RESUMEN

BACKGROUND: A variety of prophylactic materials are used in the dental office for the removal of stains and calculus. OBJECTIVE: To evaluate tooth surface changes caused by the application of air abrasive powders (sodium bicarbonate, SBAP and glycine air powder, GPAP) along with scaling and root planing (SRP), under atomic force microscope (AFM) and to analyze the histological soft tissue changes caused by these agents, using light microscopy. METHODS: This study was conducted in two phases: in vitro and in vivo. In the in vitro phase, hard tissue analysis was done under AFM following air powder polishing. Eighteen extracted teeth were chosen. SRP and tooth sectioning were carried out. Subsequently, each section of the tooth was mounted on a glass plate with self-cure acrylic resin and air polished using SBAP and GPAP. In the vivo phase, the soft tissue was analyzed under a light microscope for surface roughness. A biopsy specimen was taken from patients who had received phase I therapy, and flap surgery was planned using a modified Widman flap technique. RESULTS: This study compared surface changes in enamel and cementum, under AFM, as indicated by RA after SRP, SRP and SBAP, and SRP and GPAP; comparisons were then drawn across the three groups. The mean AFM values were 108.5 and 144.7, 102.7 and 81.7, and 95.6 and 7.4, at the crown and root, for SRP, SRP and SBAP, and SRP and GPAP interventions, respectively. GPAP was the least rough on soft tissues. CONCLUSION: SBAP and GPAP were better than hand instrumentation as indicated by AFM and histological section analysis.


Asunto(s)
Glicina , Bicarbonato de Sodio , Pulido Dental , Vidrio , Humanos , Microscopía , Polvos , Propiedades de Superficie
4.
Biotech Histochem ; 95(3): 163-170, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32053010

RESUMEN

Diabetes is a metabolic disorder that damages many organs. We investigated the effects of reperfusion using lactate Ringer's solution (LR) in a diabetic animal model. Eight-week-old rats were divided into groups: control, hemorrhagic shock induced (HS), diabetes mellitus (DM), DM plus HS (DM + HS) and DM rats that received LR after HS (DM + HS + LR). HS was induced by withdrawing blood from the femoral artery and arterial pressure was maintained at 40 mm Hg for 1 h. Animals were perfused with either withdrawn blood or LR. Rats were sacrificed and hearts were collected from all groups. Histopathological studies were performed using left ventricles and western blotting analysis was performed using protein extracted from the left ventricle. Using the TUNEL assay, we found more apoptotic cells in the DM + HS group compared to the control group, whereas in animals resuscitated with LR, the number of apoptotic cells was reduced. Western blotting showed a significant reduction in apoptotic markers, cyt c, cas 9 and cas 3, and increased survival markers, pPI3K and pAKT, in the DM + HS + LR group. Reperfusion with LR may have therapeutic effects on trauma induced HS by blocking the IGF II R facilitated apoptosis pathway in diabetic rats.


Asunto(s)
Receptor IGF Tipo 2/efectos de los fármacos , Reperfusión , Lactato de Ringer/farmacología , Choque Hemorrágico/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Diabetes Mellitus Experimental , Modelos Animales de Enfermedad , Ratas , Choque Hemorrágico/metabolismo
5.
Front Plant Sci ; 7: 1828, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28008333

RESUMEN

Assessing the ability of soil microorganisms to dissolute poorly soluble native calcite to supply Ca2+ is a new area to be explored in reclaiming sodic soils by supplying adequate Ca2+ and reducing the recurrent sodicity. Hence, the present study aimed to isolate a calcite dissolving bacteria (CDB) from calcareous sodic soils and to understand the mechanism of calcite dissolution. Of the 33 CDB isolates recovered from the calcareous sodic soils of Tamil Nadu (Coimbatore, Ramnad, and Trichy), 11 isolates were screened for calcite dissolution based on titratable acidity. 16S rRNA gene sequence analysis of the three best isolates viz., SORI09, SOTI05, and SOTI06 revealed 99% similarity to Bacillus aryabhattai, 100% to B. megaterium, and 93% to Brevibacterium sp., respectively. Among them, Brevibacterium sp. SOTI06 released more Ca2+ (3.6 g.l-1) by dissolving 18.6% of the native calcite. The spectral data of FTIR also showed reduction in the intensity of calcite (55.36-41.27) by the isolate at a wave number of 1636 cm-1 which confirmed the dissolution. Besides producing organic acids (gluconic acid and acetic acid), Brevibacterium sp. SOTI06 also produced siderophore (91.6%) and extracellular polysaccharides (EPS, 13.3 µg. ml-1) which might have enhanced the calcite dissolution.

6.
J Biomed Mater Res A ; 90(2): 380-6, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18523948

RESUMEN

In vitro studies of Ti-6Al-7Nb and Ti-5Al-2Nb-1Ta alloys were carried out by treating the specimens with 10 M NaOH at 60 degrees C for 24 h and subsequently heat-treated at 600 degrees C for 1 h. After the alkali and heat treatments, and on subsequent soaking in simulated body fluid (SBF), the morphological and compositional changes on the surface of the specimens were examined using scanning electron microscope attached with an energy-dispersive electron probe X-ray analyzer. The results revealed a dense and uniform bonelike apatite layer on the surface of treated substrates immersed in SBF solution. In vivo studies were carried out in rats to evaluate osteoconduction of Ti-6Al-7Nb and Ti-5Al-2Nb-1Ta alloys surface after alkali and heat treatments compared with untreated titanium alloys as the control. The following titanium implants were prepared from these species: (1) control without implant; (2) untreated titanium implant; (3) alkali- and heat-treated implant--the implants were immersed in 10 M NaOH solution at 60 degrees C for 24 h and subsequently heated at 600 degrees C for 1 h. The specimens were inserted into the medial side of each tibia of rats. Histologically, direct bone contact with the implant surface was significantly higher in the alkali heat-treated implants than the untreated titanium implants.


Asunto(s)
Aleaciones/farmacología , Aleaciones Dentales/farmacología , Aleaciones/química , Animales , Apatitas/química , Materiales Biocompatibles , Aleaciones Dentales/química , Calor , Técnicas In Vitro , Masculino , Ortopedia , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Prótesis e Implantes , Ratas , Ratas Sprague-Dawley , Temperatura , Titanio/química
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