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1.
SAR QSAR Environ Res ; 35(5): 391-410, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38769919

RESUMEN

Alpinia officinarum is a commonly used spice with proven folk uses in various traditional medicines. In the current study, six compounds were isolated from its rhizomes, compounds 1-3 were identified as diarylheptanoids, while 4-6 were identified as flavonoids and phenolic acids. The isolated compounds were subjected to virtual screening against α-glucosidase, butyrylcholinesterase (BChE), and acetylcholinesterase (AChE) enzymes to evaluate their potential antidiabetic and anti-Alzheimer's activities. Molecular docking and dynamics studies revealed that 3 exhibited a strong binding affinity to human a α- glucosidase crystal structure compared to acarbose. Furthermore, 2 and 5 demonstrated high potency against AChE. The virtual screening results were further supported by in vitro assays, which assessed the compounds' effects on α-glucosidase, cholinesterases, and their antioxidant activities. 5-Hydroxy-7-(4-hydroxy-3-methoxyphenyl)-1-phenylheptan-3-one (2) showed potent antioxidant effect in both ABTs and ORAC assays, while p-hydroxy cinnamic acid (6) was the most potent in the ORAC assay. In contrary, kaempferide (4) and galangin (5) showed the most potent effect in metal chelation assay. 5-Hydroxy-1,7-diphenylhepta-4,6-dien-3-one (3) and 6 revealed the most potent effect as α-glucosidase inhibitors where compound 3 showed more potent effect compared to acarbose. Galangin (5) revealed a higher selectivity to BChE, while 2 showed the most potent activity to (AChE).


Asunto(s)
Acetilcolinesterasa , Alpinia , Antioxidantes , Butirilcolinesterasa , Inhibidores de la Colinesterasa , Inhibidores de Glicósido Hidrolasas , Simulación del Acoplamiento Molecular , Rizoma , Alpinia/química , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Rizoma/química , Butirilcolinesterasa/metabolismo , Acetilcolinesterasa/metabolismo , alfa-Glucosidasas/metabolismo , Relación Estructura-Actividad Cuantitativa , Flavonoides/química , Flavonoides/farmacología , Flavonoides/aislamiento & purificación , Hidroxibenzoatos/farmacología , Hidroxibenzoatos/química , Hidroxibenzoatos/aislamiento & purificación , Humanos
2.
BMC Ophthalmol ; 24(1): 21, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38225542

RESUMEN

PURPOSE: To examine the 6-month visual outcomes and complications following cataract surgery in patients with persumed trematode induced granulomatous anterior uveitis. SETTING: Assiut university hospital, Assiut, Egypt. DESIGN: This is a retrospective non comparative case series study. METHODS: Patients presenting with significant cataract secondary to uveitis caused by trematode induced anterior chamber granuloma were included in this study. Cases with active anterior uveitis, within the last 3 months preceding surgery, and those with a history of trauma, were excluded from this study. Data collected included demographic characteristics, history of the condition including when uveitis started, treatment received and history of other health conditions that may be relevant to uveitis.Complete opthalmologic examination including assessment of best corrected visual acuity (BCVA) and OCT macula, if possible, were done. These was repeated 1 week, 1 month, 3 months and 6 months after surgery. Specular microscopy was performed preoperatively and 3 months after surgery. Patients underwent cataract surgery with posterior chamber intra ocular lens and statistical analysis was performed to compare preoperative and postoperative BCVA and corneal endothelial cell counts. Postoperative complications were recorded. RESULTS: Five eyes of 5 patients were included in the study. All study eyes showed improvement in the post-operative visual acuity. A statistically significant improvement was observed in VA in the sixth postoperative month compared to the baseline measurements (p = 0.004). No statistically significant difference was observed between the preoperative and postoperative endothelial cell counts (p = 0.696). Cystoid macular edema did not occur as a postoperative complication. CONCLUSION: Visual outcomes of cataract surgery in eyes with persumed trematode induced granulametous anterior uveitis are favorable. No sight threatening complication was observed in our series.


Asunto(s)
Catarata , Facoemulsificación , Trematodos , Uveítis Anterior , Uveítis , Niño , Animales , Humanos , Estudios Retrospectivos , Uveítis/complicaciones , Uveítis Anterior/complicaciones , Uveítis Anterior/cirugía , Catarata/complicaciones , Complicaciones Posoperatorias/cirugía , Resultado del Tratamiento , Facoemulsificación/efectos adversos
3.
Sci Rep ; 14(1): 539, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38177206

RESUMEN

This paper presents a novel grease from jojoba oil and activated carbon nanoparticles (ACNPs) extracted from banana peel waste. The raw jojoba oil and ACNPs are first characterized for structural properties. Samples of jojoba grease blended with 0.5 and 1.5 wt. % ACNPs are prepared and tested for physicochemical and tribological properties as compared to plain jojoba grease. Adding ACNPs to jojoba grease improves corrosion resistance from grade 2c to 1a while increasing the dropping point from 100 to 109 °C. ACNPs enhanced the viscosity of jojoba oil by up to 33% for testing temperature range of 40-100 °C. The load-carrying capacity of jojoba grease is increased by about 60% when blended with 1.5 wt.% ACNPs. The same blending decreased both the coefficient of friction and the wear scar diameter by 38% and 24%, respectively. A customized test rig is used to test the effectiveness of the grease samples in rolling bearing lubrication in terms of vibration levels and power consumption. The novel jojoba grease proved to show exceptional reductions power consumption reaching 25%. The vibration spectra show the absence of resonant peaks at high frequencies suggesting the capability of jojoba grease to form a stable full film lubrication.

4.
SAR QSAR Environ Res ; 34(12): 1003-1021, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38014514

RESUMEN

The MET signalling pathway regulates fundamental cellular processes such as growth, division, and survival. While essential for normal cell function, dysregulation of this pathway can contribute to cancer by triggering uncontrolled proliferation and metastasis. Targeting MET activity holds promise as an effective strategy for cancer therapy. Among potential sources of anti-cancer agents, marine organisms have gained attention. In this study, we screened 47,450 natural compounds derived from marine sources within the CMNPD database against the Met crystal structure. By employing HTVS, SP, and XP docking modes, we identified three compounds (CMNPD17595, CMNPD14026, and CMNPD19696) that outperformed a reference molecule in binding affinity to the Met structure. These compounds demonstrated desirable ADME properties. Molecular Dynamics (MD) simulations for 200 ns confirmed the stability of their interactions with Met. Our findings highlight CMNPD17595, CMNPD14026, and CMNPD19696 as potential inhibitors against Met-dependent cancers. Additionally, these compounds offer new avenues for drug development, leveraging their inhibitory effects on Met to combat carcinogenesis.


Asunto(s)
Simulación de Dinámica Molecular , Neoplasias , Sitios de Unión , Detección Precoz del Cáncer , Relación Estructura-Actividad Cuantitativa , Transducción de Señal , Simulación del Acoplamiento Molecular
5.
SAR QSAR Environ Res ; 34(9): 709-728, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37665563

RESUMEN

Malaria is a lethal disease that claims thousands of lives worldwide annually. The objective of this study was to identify new natural compounds that can target two P. falciparum enzymes; P. falciparum Dihydroorotate dehydrogenase (PfDHODH) and P. falciparum phosphoethanolamine methyltransferase (PfPMT). To accomplish this, e-pharmacophore modelling and molecular docking were employed against PfDHODH. Following this, 1201 natural compounds with docking scores of ≤ -7 kcal/mol were docked into the active site of the second enzyme PMT. The top nine compounds were subjected to further investigation using MM-GBSA free binding energy calculations and ADME analysis. The results revealed favourable free binding energy values better than the references, as well as acceptable pharmacokinetic properties. Compounds ZINC000013377887, ZINC000015113777, and ZINC000085595753 were scrutinized to assess their interaction stability with the PfDHODH enzyme, and chemical stability reactivity using molecular dynamics (MD) simulation and density functional theory (DFT) calculations. These findings indicate that the three natural compounds are potential candidates for dual PfDHODH and PfPMT inhibitors for malaria treatment.


Asunto(s)
Antimaláricos , Malaria , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH , Humanos , Dihidroorotato Deshidrogenasa , Antimaláricos/farmacología , Antimaláricos/química , Simulación del Acoplamiento Molecular , Plasmodium falciparum , Simulación de Dinámica Molecular , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/química , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , Farmacóforo , Relación Estructura-Actividad Cuantitativa , Malaria/tratamiento farmacológico
6.
Eye Vis (Lond) ; 10(1): 7, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36855211

RESUMEN

BACKGROUND: Conventional mechanical or alcohol-assisted photorefractive keratectomy (PRK) techniques for correction of hyperopia and hyperopic astigmatism were associated with inconsistent results. The aim of this study is to evaluate the 12-month visual and refractive outcomes of the relatively new single-step transepithelial photorefractive keratectomy (TE-PRK) for moderate hyperopia and hyperopic astigmatism. METHODS: This is a prospective interventional study. Forty-eight eyes of 30 patients with moderate hyperopia or hyperopic astigmatism with a cycloplegic spherical equivalent refraction (SEQ) between 2.0 and 4.5 diopters (D) underwent single-step StreamLight® TE-PRK using EX500 excimer laser (Alcon Laboratories, USA). The main outcome measures were recorded at 6 and 12 months postoperatively including assessment of logarithm of the minimum angle resolution (logMAR) uncorrected and corrected distance visual acuity (UDVA, CDVA), cycloplegic refraction, corneal topographic changes as well as post-PRK peripheral haze grading. RESULTS: The mean preoperative cycloplegic SEQ was significantly reduced from 3.21 ± 0.61 D to 0.35 ± 0.04 D and 0.41 ± 0.04 D at 6 and 12 months, respectively (P < 0.001). The mean preoperative UDVA significantly improved from 0.53 ± 0.02 logMAR to 0.07 ± 0.01 logMAR and 0.08 ± 0.01 logMAR at 6 and 12 months, respectively (P < 0.001) while the mean preoperative logMAR CDVA showed non-significant change over time throughout the study (P = 0.135). At the end of the study, 41 eyes (85.4%) achieved UDVA of 20/25 or better and no eye lost any lines of CDVA. Thirty-eight eyes (79.1%) had a postoperative cycloplegic cylinder of 0.5 D or less at 12 months. The mean preoperative mean keratometry showed significant increase at 6 and 12 months postoperatively (P < 0.001) while there was no significant change between the two postoperative visits denoting topographic stability (P = 0.058). The mean postoperative Q value at 6 and 12 months showed a significant prolate shift (P < 0.001). No haze was observed in 62.5% and 85.4% of the enrolled eyes at 6 and 12 months, respectively. CONCLUSIONS: Single-step StreamLight® TE-PRK for moderate hyperopia and hyperopic astigmatism achieved acceptable visual and refractive outcomes. TRIAL REGISTRATION: (Clinicaltrials.gov): NCT05261685, 2 March 2022, retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT05261685.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38357608

RESUMEN

Background: Associations between retinal venous occlusion (RVO), elevated intraocular pressure, and glaucoma have been reported. Further investigations into structural alterations in the fellow eyes of individuals with unilateral RVO have revealed that the peripapillary retinal nerve fiber layer is thinner than in healthy eyes, suggesting that there may be systemic risk factors common to both RVO and glaucoma. We aimed to evaluate changes in peripapillary retinal nerve fiber layer thickness (pRNFLT) among individuals with unilateral branch retinal vein occlusion (BRVO). Methods: This prospective observational study recruited 30 individuals (60 eyes) with newly diagnosed unilateral BRVO and macular edema, and a control group of 30 healthy individuals (30 eyes) with no abnormalities on fundus examination or concurrent systemic comorbidities. After baseline measurements, the participants were reassessed at 6, 12, and 24 months by measuring global and sectoral pRNFLT using spectral-domain optical coherence tomography. Results: The mean age and sex distributions were comparable between the patient and control groups (both P > 0.05). When compared to fellow eyes, global and sectoral pRNFLT in eyes with BRVO were significantly higher at baseline (all P < 0.05). Over time, pRNFLT decreased dramatically, and by the conclusion of the two-year follow-up, there was a significant reduction from baseline in the affected eyes (all P < 0.05). Likewise, affected eyes experienced a significant improvement in best-corrected distance visual acuity and central macular thickness over the two-year follow-up (both P ≤ 0.001). Comparing the global and all-sector pRNFLT of fellow eyes in the patient group with those of normal eyes in the control group, there were no significant differences at any visit, except in the temporal sector, which revealed a significant reduction in pRNFLT at 24 months in the fellow eyes of patients with unilateral BRVO (P = 0.02). Conclusions: Patients with unilateral BRVO experienced a significant reduction in pRNFLT in the affected eyes and, to a lesser extent, in the fellow eyes, compared with that of the control arm, suggesting that they are prone to retinal nerve fiber layer damage. The reduction in pRNFLT in the normal fellow eyes of patients with BRVO may be attributed to age or concurrent systemic comorbidities. Further studies with long follow-up periods are required to shed light on the etiology of functional and structural changes in both the retinal nerve fiber layer and ganglion cell complex in the normal and affected eyes of patients with unilateral BRVO.

8.
Front Oncol ; 12: 933750, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36457501

RESUMEN

Zinc oxide nanomaterial is a potential material in the field of cancer therapy. In this study, zinc oxide nanospheres (ZnO-NS) were synthesized by Sol-gel method using yeast extract as a non-toxic bio-template and investigated their physicochemical properties through various techniques such as FTIR, XR, DLS, and TEM. Furthermore, free zinc ions released from the zinc oxide nanosphere suspended medium were evaluated by using the ICP-AS technique. Therefore, the cytotoxicity of ZnO nanospheres and released Zn ions on both HuH7 and Vero cells was studied using the MTT assay. The data demonstrated that the effectiveness of ZnO nanospheres on HuH7 was better than free Zn ions. Similarly, ZnO-Ns were significantly more toxic to HuH7 cell lines than Vero cells in a concentration-dependent manner. The cell cycle of ZnO-Ns against Huh7 and Vero cell lines was arrested at G2/M. Also, the apoptosis assay using Annexin-V/PI showed that apoptosis of HuH7 and Vero cell lines by ZnO nanospheres was concentration and time-dependent. Caspase 3 assay results showed that the apoptosis mechanism may be intrinsic and extrinsic pathways. The mechanism of apoptosis was determined by applying the RT-PCR technique. The results revealed significantly up-regulated Bax, P53, and Cytochrome C, while the Bcl2 results displayed significant down-regulation and the western blot data confirmed the RT-PCR data. There is oxidative stress of the ZnO nanospheres and free Zn+2 ions. Results indicated that the ZnO nanospheres and free Zn+2 ions induced oxidative stress through increasing reactive oxygen species (ROS) and lipid peroxidation. The morphology of the HuH7 cell line after exposure to ZnO nanospheres at different time intervals revealed the presence of the chromatin condensation of the nuclear periphery fragmentation. Interestingly, the appearance of canonical ultrastructure features of apoptotic morphology of Huh7, Furthermore, many vacuoles existed in the cytoplasm, the majority of which were lipid droplets, which were like foamy cells. Also, there are vesicles intact with membranes that are recognized as swollen mitochondria.

10.
J Multidiscip Healthc ; 14: 1935-1944, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34326644

RESUMEN

PURPOSE: To evaluate the ocular manifestations of post-acute COVID-19 syndrome. METHODS: A retrospective, comparative study included 100 patients who had recovered from COVID-19 and 100 controls who were recruited by stratified randomization from hospital registration system and analyzed regarding history, full ophthalmological examination, general examination including internal medicine and neurological evaluation. Laboratory tests were done. RESULTS: Mean±SD of age were 55.5 ± 6.2 in COVID group vs 56.5 ± 5.8 in control group; P value = 0.7. In COVID group, 57 patients (57%) were males vs 51 patients (51%) in control group (P value = 0.39), the other compared parameters including history and risk factors showed non-significant difference except for ESR and D-dimer which were elevated in COVID group. In COVID group, 5 patients (5%) were having retinal vascular occlusion, 2 patients (2%) were having anterior ischemic optic neuropathy AION, 3 patients (3%) were having uveitis and 2 patients (2%) were having central serous chorioretinopathy CSCR. While in control group, 2 patients (2%) were having retinal vascular occlusion, and none had AION, uveitis or CSCR (P value = 0.006). CONCLUSION: Post-acute COVID-19 syndrome could affect the eyes in the form of coagulation problems, neurological morbidities, and other manifestations. This necessitates meticulous follow-up of recovered patients from COVID-19.

11.
Clin Ophthalmol ; 15: 1583-1589, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33888974

RESUMEN

PURPOSE: To demonstrate the demographic features, causative agents, and outcome of pediatric traumatic cataract surgery in eyes without posterior segment involvement at Assiut University Hospital, Upper Egypt. PATIENTS AND METHODS: This is a retrospective study on children (aged <18 years old) who underwent traumatic cataract surgery from January to June 2019. Children with posterior segment injury and those who did not complete 6 months of postoperative follow-up were excluded. The demographic features, mechanism and time of eye injury, clinical features, surgical approach, and outcome were recorded and analyzed. RESULTS: The study included 34 eyes of 34 children, 23 (68%) of them were boys. The mean age at the time of cataract surgery was 10±3.97 years. Twenty-one eyes sustained open globe injury (62%) with the most common cause of trauma was wooden sticks, while 13 eyes had closed globe injury (38%) with the most common cause of injury was thrown stones. The time interval between eye injury and cataract surgery ranged from 1 day to 9 years with a median of 2.05 months. Posterior chamber intraocular lenses were implanted in all eyes; in 33 eyes, the posterior chamber intraocular lenses were implanted primarily at the time of cataract extraction. Corrected distance visual acuity significantly improved from 2.63±0.66 LogMAR preoperatively, to 0.41±0.38 LogMAR postoperatively (p < 0.001). CONCLUSION: Pediatric traumatic cataract is commonly present in primary school age especially after open globe injury. Primary prevention through health awareness should target this age population. Useful vision can be regained with timely proper surgical intervention and posterior chamber intraocular lens implantation. CLINICALTRIALSGOV ID: NCT04630509.

12.
Macromol Biosci ; 21(1): e2000317, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33043610

RESUMEN

Bioinks play a key role in determining the capability of the biofabricatoin processes and the resolution of the printed constructs. Excellent biocompatibility, tunable physical properties, and ease of chemical or biological modifications of gelatin methacryloyl (GelMA) have made it an attractive choice as bioinks for biomanufacturing of various tissues or organs. However, the current preparation methods for GelMA-based bioinks lack the ability to tailor their physical properties for desired bioprinting methods. Inherently, GelMA prepolymer solution exhibits a fast sol-gel transition at room temperature, which is a hurdle for its use in stereolithography (SLA) bioprinting. Here, synthesis parameters are optimized such as solvents, pH, and reaction time to develop GelMA bioinks which have a slow sol-gel transition at room temperature and visible light crosslinkable functions. A total of eight GelMA combinations are identified as suitable for digital light processing (DLP)-based SLA (DLP-SLA) bioprinting through systematic characterizations of their physical and rheological properties. Out of various types of GelMA, those synthesized in reverse osmosis (RO) purified water (referred to as RO-GelMA) are regarded as most suitable to achieve high DLP-SLA printing resolution. RO-GelMA-based bioinks are also found to be biocompatible showing high survival rates of encapsulated cells in the photocrosslinked gels. Additionally, the astrocytes and fibroblasts are observed to grow and integrate well within the bioprinted constructs. The bioink's superior physical and photocrosslinking properties offer pathways of tuning the scaffold microenvironment and highlight the applicability of developed GelMA bioinks in various tissue engineering and regenerative medicine applications.


Asunto(s)
Bioimpresión , Gelatina/farmacología , Metacrilatos/farmacología , Estereolitografía , Ingeniería de Tejidos , Supervivencia Celular/efectos de los fármacos , Gelatina/síntesis química , Gelatina/efectos de la radiación , Humanos , Hidrogeles/química , Hidrogeles/farmacología , Tinta , Luz , Metacrilatos/síntesis química , Metacrilatos/efectos de la radiación , Impresión Tridimensional , Andamios del Tejido/química
13.
J Biomed Mater Res B Appl Biomater ; 109(5): 622-629, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32945089

RESUMEN

Polyether ether ketone (PEEK) has shown great promise for implant and biomedical applications because of its excellent chemical, mechanical, and biocompatible properties. However, PEEK is bioinert, which causes weak cell adhesion and limits its use for biomedical applications such as bone implants. Therefore, the activation of the PEEK's surface for cell attachment is desirable. In this study, oxygen plasma and gelatin were used to modify PEEK's surface and the effects of surface roughness, wettability, and cell adhesion to the surface were studied. Surface roughness was measured using a laser scanning confocal microscope, and wettability was measured using the sessile drop method. There was no significant difference in the roughness of the three samples. The gelatin-coated surface showed higher wettability than the plasma-modified or control samples. The cell attachment and proliferation rate were assessed by scanning electron microscopy and the XTT assay, respectively. The XTT assay results indicated that a greater number of cells grew on the gelatin-coated PEEK surface than on the control or plasma-treated surfaces. These results confirmed that the plasma and gelatin treatments enhanced the biocompatibility of the PEEK samples. The increase in biocompatibility could make PEEK a better material candidate for treating bone related injuries and defects.


Asunto(s)
Benzofenonas/química , Cetonas/química , Polímeros/química , Animales , Materiales Biocompatibles/química , Adhesión Celular/efectos de los fármacos , Proliferación Celular , Gelatina/farmacología , Ratones , Microscopía Confocal , Microscopía Electrónica de Rastreo , Células 3T3 NIH , Osteoblastos/citología , Osteogénesis/efectos de los fármacos , Oxígeno/química , Polietilenglicoles/química , Prótesis e Implantes , Propiedades de Superficie , Titanio/química , Humectabilidad
14.
Clin Ophthalmol ; 14: 3495-3498, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33149542

RESUMEN

PURPOSE: To evaluate the safety and efficacy of topical difluprednate ophthalmic emulsion use for prophylaxis of corneal graft rejection in patients undergoing penetrating keratoplasty. METHODS: This study reviewed the charts of patients undergoing penetrating keratoplasty who were treated with difluprednate (DP) ophthalmic emulsion postoperatively. At each follow-up visit, patients were followed for signs of graft rejection, cataract development, and intraocular pressure rise in addition to routine ocular examination. RESULTS: The charts of 36 patients (38 eyes) who underwent penetrating keratoplasty (PKP) (27 eyes) and PKP triple (11 eyes) were reviewed. All eyes were followed up for at least 8 months postoperatively. Five grafts developed rejection and three grafts subsequently failed. Six eyes had an increase of IOP that required use of antiglaucoma drops. Three eyes were switched from difluprednate to prednisolone acetate (PA) after persistent rise of IOP failed to respond to antiglaucoma drops. None of these cases needed glaucoma surgery. Two patients developed cataract during the follow-up period (out of 12 phakic eyes). CONCLUSION: Topical difluprednate is potentially effective and safe in preventing graft rejection after penetrating keratoplasty. Larger prospective clinical trials are warranted.

15.
Small ; 16(30): e2000941, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32588966

RESUMEN

Cells in vivo are constantly subjected to multiple microenvironmental mechanical stimuli that regulate cell function. Although 2D cell responses to the mechanical stimulation have been established, these methods lack relevance as physiological cell microenvironments are in 3D. Moreover, the existing platforms developed for studying the cell responses to mechanical cues in 3D either offer low-throughput, involve complex fabrication, or do not allow combinatorial analysis of multiple cues. Considering this, a stretchable high-throughput (HT) 3D cell microarray platform is presented that can apply dynamic mechanical strain to cells encapsulated in arrayed 3D microgels. The platform uses inkjet-bioprinting technique for printing cell-laden gelatin methacrylate (GelMA) microgel array on an elastic composite substrate that is periodically stretched. The developed platform is highly biocompatible and transfers the applied strain from the stretched substrate to the cells. The HT analysis is conducted to analyze cell mechano-responses throughout the printed microgel array. Also, the combinatorial analysis of distinct cell behaviors is conducted for different GelMA microenvironmental stiffnesses in addition to the dynamic stretch. Considering its throughput and flexibility, the developed platform can readily be scaled up to introduce a wide range of microenvironmental cues and to screen the cell responses in a HT way.


Asunto(s)
Bioimpresión , Ensayos Analíticos de Alto Rendimiento , Gelatina , Hidrogeles , Metacrilatos , Impresión Tridimensional
16.
Mater Sci Eng C Mater Biol Appl ; 111: 110754, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32279821

RESUMEN

Over the past decades, inorganic nanoparticles (NPs), particularly metal oxide NPs, have attracted great attention due to their strong bactericidal effects. Researchers have used NPs to fabricate nanocomposite materials which have innate antibacterial capability. Herein, we present a straightforward method to fabricate antibacterial nanocomposites. Ag, TiO2, and ZnO NPs were dispersed within liquid silicone rubber (LSR) structure in four concentrations. Three different methods were used to evaluate the antibacterial efficiency of the NPs forming the nanocomposite materials: (I) the diffusion method, (II) agar counting plate, and (III) a live/dead assay of E. coli. The mechanical properties and hydrophobicity of the nanocomposites were characterized and correlated to the antibacterial efficiency of the NPs. In order to test the antibacterial efficiency in a high-throughput, cost-effective and efficient manner, a microfluidic device fabricated by 3D printing and soft-lithography methods was used. The LSR-15 wt% TiO2 nanocomposites showed the best antibacterial efficiency. In addition, TiO2 NPs formed the stiffest nanocomposites with very fine, even surface which increased the hydrophobicity of the surface where bacteria attach to grow, preventing bacteria from further growth.


Asunto(s)
Antibacterianos/química , Dispositivos Laboratorio en un Chip , Nanocompuestos/química , Polímeros/química , Antibacterianos/farmacología , Pruebas Antimicrobianas de Difusión por Disco , Escherichia coli/efectos de los fármacos , Nanopartículas del Metal/química , Nanocompuestos/toxicidad , Plata/química , Titanio/química , Óxido de Zinc/química
17.
Biomicrofluidics ; 14(2): 021501, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32161630

RESUMEN

Microfluidic principles have been extensively utilized as powerful tools to fabricate controlled monodisperse cell-laden hydrogel microdroplets for various biological applications, especially tissue engineering. In this review, we report recent advances in microfluidic-based droplet fabrication and provide our rationale to justify the superiority of microfluidics-based techniques over other microtechnology methods in achieving the encapsulation of cells within hydrogels. The three main components of such a system-hydrogels, cells, and device configurations-are examined thoroughly. First, the characteristics of various types of hydrogels including natural and synthetic types, especially concerning cell encapsulation, are examined. This is followed by the elucidation of the reasoning behind choosing specific cells for encapsulation. Next, in addition to a detailed discussion of their respective droplet formation mechanisms, various device configurations including T-junctions, flow-focusing, and co-flowing that aid in achieving cell encapsulation are critically reviewed. We then present an outlook on the current applications of cell-laden hydrogel droplets in tissue engineering such as 3D cell culturing, rapid generation and repair of tissues, and their usage as platforms for studying cell-cell and cell-microenvironment interactions. Finally, we shed some light upon the prospects of microfluidics-based production of cell-laden microgels and propose some directions for forthcoming research that can aid in overcoming challenges currently impeding the translation of the technology into clinical success.

18.
Lab Chip ; 19(9): 1621-1632, 2019 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-30896015

RESUMEN

We present the development of a stable continuous, and integrated microfluidic platform for the high-throughput fabrication of monodisperse cell-laden microgel droplets with high and maintained cellular viability. This is through combining onto one chip all the required processes from the droplet generation in a flow focusing microfluidic junction passing through on-chip photocrosslinking to the separation of the droplets from the continuous oil phase. To avoid cellular aggregation during the droplet generation process, cells were treated with bovine serum albumin (BSA) before mixing with gelatin methacrylate (GelMA). And, a magnetic mixer was applied to the GelMA prepolymer-cell suspension syringe to eliminate cell sedimentation. These approaches resulted in having a reasonable distribution of cells among monodisperse microdroplets. The microdroplets were irradiated with a 405 nm wavelength laser beam while passing through the crosslinking chamber of the microfluidic device. The produced microgels enter the filtration unit of the same device where they were gently separated from the oil phase into the washing buffer aqueous solution of Tween 80 using the filter microposts array. The viability of the encapsulated cells was around 85% at day 1 and was maintained throughout 5 days. Using this method of controlling cell encapsulation with on-chip crosslinking and oil filtration, highly efficient cell-laden microgel production is achieved. The presented integrated microfluidic platform can be a candidate for standard cell-encapsulation experiments and other tissue engineering applications.


Asunto(s)
Filtración/instrumentación , Dispositivos Laboratorio en un Chip , Integración de Sistemas , Animales , Supervivencia Celular , Gelatina/química , Geles , Metacrilatos/química , Ratones , Células 3T3 NIH , Albúmina Sérica Bovina/química
19.
Retin Cases Brief Rep ; 13(2): 154-157, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-28145942

RESUMEN

BACKGROUND/PURPOSE: To describe a case of histopathologic clinical correlation of sarcoidosis-related multifocal chorioretinitis in an elderly individual. METHODS: This is a single case report and review of the pertinent literature. A 72-year-old white woman with a history of asthma was referred with bilateral asymmetric low-grade chronic panuveitis with advancing peripheral punched-out chorioretinal lesions despite systemic corticosteroid treatment. RESULTS: Coalescent chorioretinal punched-out lesions on fundus examination in the more severely affected right eye did not respond to corticosteroid treatment, and the refractory nature resulted in a suspicion of intraocular lymphoma despite a previous inconclusive diagnostic vitrectomy result. A transvitreal chorioretinal biopsy in the vitrectomized eye demonstrated a chorioretinal noncaseating granuloma centered on the choriocapillaris and invading Bruch membrane and the outer retina. This case illustrates an example of the second peak of incidence in sarcoidosis that can occur in ages >50 in Caucasians and Japanese patients, as well as a tendency to develop chronic disease in Caucasians, and to have extrapulmonary sarcoidosis in the elderly. CONCLUSION: This case emphasizes the differences in presentation of ocular sarcoid in older Caucasian women as well as the histopathologic findings in multifocal peripheral chorioretinitis associated with sarcoidosis.


Asunto(s)
Coriorretinitis/patología , Sarcoidosis/patología , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Panuveítis/patología
20.
Cornea ; 38(1): 93-97, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30272616

RESUMEN

PURPOSE: To evaluate the role of swept-source anterior segment optical coherence tomography (AS-OCT) in the diagnosis and management of laser in situ keratomileusis (LASIK) flap-related complications. METHODS: This prospective study included 25 eyes with LASIK flap-related complications imaged using swept-source AS-OCT between February and August 2016 at Alforsan Eye Centre, Assiut, Egypt. The images were acquired using a 6-mm line scan. RESULTS: Imaging of flap-related LASIK complications using AS-OCT revealed specific and nonspecific findings. Of note, epithelial ingrowth appeared as highly reflective lesions below the LASIK flap in the form of islands, nests, or a continuous sheet with or without changes in the overlying flap. Macrostriae manifested as dome-shaped irregularities on the stromal surface with regular overlying epithelium, whereas microstriae appeared as corrugations on the stromal surface with regular overlying epithelium. Less common complications included multiple flap macrostriae accompanied by a traumatic folded flap with a flap edge at the interface. Interface debris appeared as a highly reflective interface lesion with or without a surrounding reaction. One eye with a flap that was torn and lost intraoperatively showed epithelialization over a thin residual stroma underlying a contact lens with no stromal infiltration on the second postoperative day. AS-OCT was useful for the assessment of flap thickness and planning of the new flap thickness in the event of an incomplete cut. CONCLUSIONS: Swept-source AS-OCT is useful not only for diagnosis but also for management of eyes with LASIK flap-related complications by allowing noninvasive, noncontact, real-time acquisition of cross-sectional AS images.


Asunto(s)
Córnea/patología , Queratomileusis por Láser In Situ/efectos adversos , Miopía/cirugía , Complicaciones Posoperatorias/diagnóstico , Colgajos Quirúrgicos/efectos adversos , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Complicaciones Posoperatorias/cirugía , Estudios Prospectivos , Reoperación
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