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Objective To verify the biomechanical stability of oblique lateral interbody fusion ( OLIF) combinedwith different fixation methods for treating degenerative lumbar scoliosis (DLS) by three-dimensional (3D) finite element analysis. Methods The L1-S1 3D finite element DLS model ( Model 1) was established, and then the OLIF (L2-5) at 3 contiguous levels of fusion and its combination with different internal fixation methods were simulated, namely, stand-alone OLIF model ( Model 2), vertebral screw fixation model ( Model 3), unilateral pedicle screw fixation model (Model 4) and bilateral pedicle screw fixation model (Model 5) were established,respectively. Under upright, flexion, extension, lateral bending and axial rotation states, range of motion (ROM) of fusion segments, as well as cage stress, internal fixation stress, and stress distribution were recorded and analyzed. Results Under six motion states, the overall ROM of fusion segments in Models 2-5 was smaller than that of Model 1. Compared with Model 1, the overall ROM reduction of Model 3 and Model 4 was larger than that of Model 2 and smaller than that of Model 5. Under flexion and extension, the overall ROM reduction of Model 4 and Model 5 was basically equal. Under left and right lateral bending, the overall ROM reduction of Model 3 and Model 5 was basically equal. Under all motion states, the peak stress of Model 3 and Model 4 fusion cage was larger than that of Model 5 and smaller than that of Model 2. The peak stresses of L2-3, L3-4 and L4-5 fusion cages in Model 3 increased by 5. 52% , 10. 96% and 7. 99% respectively compared with Model 5 under left lateral bending, and the peak stresses of L2-3, L3-4 and L4-5 fusion cages in Model 4 increased by 8. 70% , 7. 00% and 6. 99% respectively under flexion. Under all motion states, the peak stress of screw rod in Model 5 was smaller than that of Model 3 and Model 4, and the peak stresses of screw rod in Models 3-5 were the smallest in upright state. Conclusions The OLIF with unilateral pedicle screw fixation or vertebral screw fixation can provide favorable biomechanical stability of the fusion segment. The results provide some references for clinical application of OLIF technology in the treatment of DLS.
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Plant mediated green synthesis of silver nanoparticles (AgNPs) holds promising applications in the field of Biomedicine, Food packaging and Wound healing. In the present investigation, biofabrication of AgNPs was performed using the aqueous extracts of Campsis sp. (Family Bignoniaceae) leaves and flowers growing in the premises of Kirori Mal College, University of Delhi, Delhi. Optimization of AgNPs was performed to analyse the varying effect of pH (6.0, 8.0, 10.0) and silver salt concentration (2mM, 4Mm and 6Mm) in controlling the shape and size of AgNPs which in turn governs their further applications. Interestingly, change in colour of the reaction mixture from pale yellow to reddish brown indicated the formation of AgNPs. These AgNPs were further characterized by UV-Visible spectroscopy and showed peak in the range of 400-450 nm which confirmed the synthesis of silver nanoparticles. Dynamic light scattering and zeta potential analysis (DLS-Zeta) confirmed the size of AgNPs around 200-300 nm. A significant zone of inhibition was observed for both Staphylococcus aureus (gram-positive) and Escherichia coli (gram-negative) bacterial strains which revealed the antimicrobial potential of Campsis sp. AgNPs. Therefore, Campsis AgNPs may provide a green, eco-sustainable alternate method for sustainable production of nanomaterials for biomedical applications. These AgNPs may also show tremendous applications in food packaging, wound healing and biomedical fields.
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Photothermal therapy has the characteristics of minimal invasiveness, controllability, high efficiency, and strong specificity, which can effectively make up for the toxic side effects and tumor resistance caused by traditional drug treatment. However, due to the limited tissue penetration of infrared light, it is difficult to promote and apply in clinical practice. The eye is the only transparent tissue in human, and infrared light can easily penetrate the eye tissue, so it is expected that photothermal therapy can be used to treat fundus diseases. Here in, a new nano-platform assembled by liposome and indocyanine green (ICG) was used to treat retinoblastoma. ICG was assembled in liposomes to overcome some problems of ICG itself. For example, ICG is easily quenched, self-aggregating and instability. Moreover, liposomes can prevent free ICG from being cleared through the systemic circulation. The construction of the nano-platform not only ensured the stability of ICG in vivo, but also realized imaging-guide photothermal therapy, which created a new strategy for the treatment of retinoblastoma.
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Objetivo: Investigar la aplicación del niosoma como nanoportador de extracto de salvia (Salvia officinalis L.) mediante espectroscopia y quimiometría. Material y método: En este estudio, se prepararon nanopartículas de niosoma que contienen colesterol y sin colesterol mediante el método de hidratación de película fina. El extracto etanólico de salvia se extrajo mediante microondas y se cargó dentro de las nanopartículas de niosoma. El tamaño de las nanopartículas se determinó mediante microscopía electrónica de barrido de imágenes de campo (FE-SEM). El potencial zeta de los niosomas se determinó mediante dispersión dinámica de luz (DLS). Para investigar el tipo de interacciones entre los tensioactivos y el colesterol utilizados en la estructura del niosoma, se utilizó la espectroscopia infrarroja por transformada de Fourier (FT-IR). Se investigó la liberación de fármaco durante 5 días consecutivos en tampón fosfato salina (PBS) 0/01 M con pH = 7,4 a T = 37ºC. Resultados: El potencial zeta de los niosomas con colesterol y sin colesterol fue de -24 / 1 y -15 / 6 mv. La capacidad de carga del fármaco en el rango de concentración (1-3% p / p de niosum) para ambos tipos de niosoma estuvo entre 61% y 93%. Conclusión: Estos resultados muestran que la tasa de liberación de niosma con colesterol es significativamente más regular y más baja que la de niosoma sin colesterol. En general, se puede concluir que el niosoma puede ser un nanoportador adecuado para el suministro de extracto hidrófilo de la salvia.
Objetive:Investigation the application of niosome as a nanocarrier for sage (Salvia officinalis L.) extract by spectroscopy and chemometrics. In this Material and Method:study,niosomenanoparticlescontainingcholesterolandwithoutcholesterolwere prepared by thin film hydration method. Ethanol extract of sage was extracted by microwave and loaded inside the niosome nanoparticles. The size of the nanoparticles was determined by field imaging scanning electron microscopy (FE-SEM). The zeta potential of the niosomes was determined by Dynamic light scattering (DLS). to investigate the type of interactions between surfactants and cholesterol used in the niosome structure, Fourier transform infrared spectroscopy (FT-IR) was used. Drug release was investigated for 5 consecutive days in phosphate buffer salin (PBS) 0/01 M with pH=7.4 at T=370C. The zeta potential of the niosomes with cholesterol and without Results:cholesterol was -24/1&-15/6 mv . The loading capacity of the drug in the concentration range (1-3% w / w of niosum) for both types of niosome was between 61% and 93%. Conclusion:This results show that the release rate of niosme with cholesterol is significantly more regular and lower than of niosome without cholesterol. In general, it can be concluded that niosome can be a suitable nano-carrier for delivery of hydrophilic extract of the sage.
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Background: Yashada bhasma has been found to be very useful for the treatment of ailments like diabetes, eye disorder, urinary disorder etc. Since bhasma is a metallic preparation, so to prove its nontoxicity; modern standardization of the prepared samples is a must apart from other organoleptictests as mentioned in the ancient text.Objectives: The present study is aimed to synthesize bio-compatible Yashada bhasma from bioincompatible zinc metal. Further, comparative study of their chemical and physical properties throughsome quality control tests, physico-chemical tests and modern tests like XRD, DLS, Zeta potential, SEMand EDAX are carried out.Materials and methods: Yashada bhasma is prepared by a three step process i.e. Shodhan, Jarana andMarana. The inclusion of plant extracts and herbs during calcination process enhances its medicinalqualities, and reduces it to a nano size.Results: The XRD analysis of Yashada bhasma shows hexagonal ZnO crystalline phase whereas the rawmetal confirms the presence of crystallite Zinc metal. DLS shows reduction in particle size of YashadaBhasma (339.8 nm) as compared to raw metal (2063 nm) and this reduction is further supported by SEMwhich shows the particle size of Yashada bhasma (324 nm) and raw metal (1-2m). The zeta potential valueconfirms the stability of Yashada bhasma. EDAX revealed difference in concentration of Zinc and Oxygenin both the samples.Conclusion: An effort has been made to characterize the preparation of Yashada bhasma using sophisticated analytical tools as a step towards standardization of the bhasma. The results help in scientificallyestablishing the findings in line with the principle of Ayurveda.
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This study aimed to explore the link between block copolymers' interfacial properties and nanoscale carrier formation and found out the influence of length ratio on these characters to optimize drug delivery system. A library of diblock copolymers of PEG-PCL and triblock copolymers with additional PEI (PEG-PCL-PEI) were synthesized. Subsequently, a systematic isothermal investigation was performed to explore molecular arrangements of copolymers at air/water interface. Then, structural properties and drug encapsulation in self-assembly were investigated with DLS, SLS and TEM. We found the additional hydrogen bond in the PEG-PCL-PEI contributes to film stability upon the hydrophobic interaction compared with PEG-PCL. PEG-PCL-PEI assemble into smaller micelle-like (such as PEG-PCL4006-PEI) or particle-like structure (such as PEG-PCL8636-PEI) determined by their hydrophilic and hydrophobic block ratio. The distinct structural architectures of copolymer are consistent between interface and self-assembly. Despite the disparity of constituent ratio, we discovered the arrangement of both chains guarantees balanced hydrophilic-hydrophobic ratio in self-assembly to form stable construction. Meanwhile, the structural differences were found to have significant influence on model drugs incorporation including docetaxel and siRNA. Taken together, these findings indicate the correlation between molecular arrangement and self-assembly and inspire us to tune block compositions to achieve desired nanostructure and drug loading.
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Introduction: The biological green synthesis of nanoparticles via nanobiotechnology processes have a significant potential to boost nanoparticles production without the use of harsh, toxic, and expensive chemicals commonly used in conventional physical and chemical processes. Annona muricata, a tropical plant belonging to family Annonaceae is one of the most used plants in folk medicine because of its many medicinal uses and therefore presents a strong candidate for use in green synthesis. Aims: The aim of this study was to optimize a method for the synthesis of Silver Nanoparticles (AgNPs) from ethanolic extracts of leaves of Annona muricata as well as to characterize the green synthesized AgNPs. Methodology: AgNPs were synthesized from Annona muricata leaves using AgNO3 solution. The AgNPs were characterized using spectroscopy and microscopy techniques. Results: The formed AgNPs had an absorption maximum at 429 nm using UV–Visible spectroscopy and were stable under different pH, temperature, and storage conditions. Fourier transform infrared analysis revealed the different functional groups responsible for the synthesis and stabilization of the AgNPs. Scanning electron microscopy analysis revealed a spherical nature of the synthesized AgNPs. Energy dispersive x-ray spectroscopy analysis showed presence of Ag, O, and Cl with Ag having the highest composition at 60%. X-Ray Diffraction and Dynamic Light Scattering revealed a crystalline nature of AgNPs with an average size of 87.36 nm and a polydispersity index of 0.16 respectively. Transmission Electron Microscopy analysis further confirmed the crystalline and spherical nature of the AgNPs. Conclusion: In this article, an efficient, eco-friendly and low-cost method for the synthesis and recovery of stable AgNPs using Annona muricata leaves ethanolic extracts as both a reducing and capping agent has been reported for the first time. The synthesized AgNPs could be promising candidates for many biomedical, clinical, engineering, and polymer applications.
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Objective: To express a cost efficacious and environment friendly method for the green synthesis of silver nanoparticles (AgNPs) from Catharanthus roseus var. alba (C. roseus var. alba) callus extract. Methodology: The aqueous solution of sliver nitrate containing Ag+ ions (1 mM) are integrating 100 μL of aqueous extract of callus of C. roseus var. alba and 10 mL of 1% w/v aqueous solution of polyethylene glycol 4000 to 90 mL. This was then alkalized with 0.1 NaOH (20 μL) and treated in a microwave oven (800 W) for 40 sec for the reduction of metal ion and the reaction takes place at room temperature (250C). The reduction of the Ag+ ions by aqueous callus extract of C. roseus var. alba in the solutions was monitored by UV–Visible spectrum and further characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM) and x-ray diffraction (XRD). Antibacterial activity was assessed on bacterial strain of Staphylococcus aureus and Pseudomonas aeruginosa (S. aureus and P. aeruginosa) by using the disc-diffusion assay method. Results: Characterization of AgNPs was done DLS, TEM and XRD methods. The Dynamic Light Scattering (DLS) showed the particle size distribution of the AgNPs synthesized from C. roseus var. alba callus extract was found 86.95 nm with polydispersity index (PDI) value of = 0.304. TEM images showed the formation of AgNPs with an average size of 10 nm to 20 nm. And the XRD analysis showed that the AgNPs were crystalline in nature with face-centered-cubic (FCC). For the assessment of antibacterial activity the concentration of AgNPs 25 μL, 50 μL, 100 μL and 150 μL were used against both the bacterial strain S. aureus and P. aeruginosa, the zone of inhibition found 4 mm, 7 mm, 16 mm and 23 mm as well as 5 mm, 9 mm, 19 mm and 26 mm respectively. Conclusions: Aseptically engendered callus of C. roseus var. alba demonstrates vigorous potential for synthesis of silver nanoparticles by rapid reduction of Ag+ to Ag. The biologically synthesized AgNPs showed more preponderant antibacterial effect against S. aureus and P. aeruginosa.
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Esta investigación identifica los factores de la gestión que afectan las acciones de promoción y prevención en el régimen subsidiado de un municipio del Valle del Cauca. Se recolecta información en la dirección local de salud, la empresa social del Estado y dos administradoras del régimen subsidiado, sobre el sistema de contratación y la capacidad operativa en el período correspondiente entre abril del 2002 y marzo del 2003. La interpretación de los resultados se realiza con base en una escala devaloración donde los valores más bajos denominados precarios, los intermedios potenciales y los altos avanzados. La contratación en la dirección local de salud es precaria, en la empresa social del estado, potencial. En la administradora del régimen subsidiado No.1 y la administradora del régimen subsidiado No.2 es potencial y precaria respectivamente. La valoración de lacapacidad operativa en las cuatro instituciones arroja gran variabilidad en los indicadores de la planeación, organización, dirección y ejecución. Los resultados muestran poca articulación entre los actores responsablesde la planeación, dirección y ejecución de las acciones de promoción y prevención, falencias en el seguimiento y evaluación de estas acciones y profallas en los entes territoriales frente a los procesos de vigilancia y control que la ley les confiere.