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61.
In the present study, we fabricated an efficient, simple biomimetic scaffold to stimulate osteogenic differentiation of mesenchymal stem cells (MSCs). Electrospun poly L-lactic acid nanofibers were employed to mimic the nanofibrillar structure of bone proteins and coated with hydroxyapatite nanoparticles to simulate bone minerals. Thereafter, we regulated the release pattern of BMP-2 peptide through covalent attachment of an optimized liposomal formulation to the scaffold. The fabricated platform provided a sustained release profile of BMP-2 peptide up to 21?days while supporting cellular attachment and proliferation without cytotoxicity. In-vitro results confirmed the superiority of the scaffold containing liposomes through enhancement of growth and differentiation of MSCs. Ectopic bone formation model exhibited significant localized initiation of bone formation of liposome incorporated scaffold. Consequently, these findings demonstrated that our designed platform with modified release properties of BMP-2 peptide considerably promoted osteogenic differentiation of MSCs making it a unique candidate for bone regeneration therapeutics.  相似文献   
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OBJECTIVE: The purpose of this study was to compare the antimicrobial effect of AH-26, RealSeal (RS), and GuttaFlow after 24 hours and after one week. METHODOLOGY: All sealers were prepared according to the manufacturers' directions immediately before testing. The microorganisms used in this assay included Staphylococcus aureus and Streptococcus mutans, which were prepared from isolated species in the microbiology laboratory. The antimicrobial effects of each sealer were determined by measuring the diameter of the zone of inhibition in millimeters after incubation at 37 degrees C for 24 hours and for seven days in a humid atmosphere. Each test was repeated three times. RESULTS: In the 24-hour samples, as well as in seven-day samples, the antibacterial activity of AH-26 was significantly greater than two other materials tested against both bacteria (p < 0.05). The antibacterial activities of RS and GuttaFlow against Staphylococcus aureus were not significantly different from each other (p > 0.05) in 24-hour as well as seven-day samples, but RS had significantly greater effect against Streptococcus mutans than GuttaFlow (p < 0.05). CONCLUSION: The products studied exhibited some variable antibacterial properties. In 24 hours, as well as in seven days, the AH-26 exerted the greatest activity against both organisms tested.  相似文献   
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Nanotechnology‐based drug delivery systems can enhance drug permeation through the skin and improve the drug stability. The biodegradability and biocompatibility of cellulose nanocrystals have made these nanoparticles good candidates to use in biomedical applications. The hyperpigmentation is a common skin disorder that could be caused by number of reasons such as sun exposure and pregnancy. Hydroquinone could inhibit the production of melanin and eliminate the discolorations of skin. This study is aimed at introducing cellulose nanocrystals as suitable carriers for drug delivery to skin. Prepared cellulose nanocrystals were characterized by dynamic light scattering and atomic force microscopy. The size of cellulose nanocrystals determined using dynamic light scattering was 301 ± 10 nm. Hydroquinone–cellulose nanocrystal complex was prepared by incubating of hydroquinone solution in cellulose nanocrystals suspension. The size of hydroquinone–cellulose nanocrystal complex determined using dynamic light scattering was 310 ± 10 nm. The hydroquinone content of the hydroquinone–cellulose complex was determined using UV/vis spectroscopy. Hydroquinone was bound to cellulose nanocrystals representing 79.3 ± 2% maximum binding efficiency when 1.1 mg hydroquinone was added to 1 mL of cellulose nanocrystals suspension (2 mg cellulose nanocrystal). The hydroquinone–cellulose nanocrystal complex showed an approximately sustained release profile of hydroquinone. Approximately, 80% of bound hydroquinone released in 4 h.  相似文献   
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Background Involving service users and carers in decisions about their health care is a key feature of health‐care practice. Professional health and social care students need to develop skills and attributes to best enable this to happen. Aims The aims were to explore service user and carer perceptions of behaviours, attributes and context required to enable shared decision making; to compare these perceptions to those of students and academic staff with a view to utilizing the findings to inform the development of student assessment tools. Methods A mixed methods approach was used including action learning groups (ALG) and an iterative process alongside a modified Delphi survey. Participants The ALGs were from an existing service user and carer network. The survey was sent to sixty students, sixty academics and 30 service users from 16 different professional disciplines, spanning four Universities in England. Results The collaborative enquiry process and survey identified general agreement that being open and honest, listening, showing respect, giving time and being up to date were important. The qualitative findings identified that individual interpretation was a key factor. An unexpected result was an insight into possible insecurities of students. Conclusions The findings indicate that distilling rich qualitative information into a format for student assessment tools could be problematic as the individual context could be lost, it is therefore proposed that the information could be better used as a learning rather than assessment tool. Several of those involved identified how they valued the process and found it beneficial.  相似文献   
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A series of new Schiff bases bearing 1,2,3‐triazole 12a ? o was designed, synthesized, and evaluated as α‐glucosidase inhibitors. All the synthesized compounds showed promising inhibition against α‐glucosidase and were more potent than the standard drug acarbose. The kinetic study on the most potent compound 12n showed that this compound acted as a competitive α‐glucosidase inhibitor. The docking study revealed that the synthesized compounds interacted with the important residues in the active site of α‐glucosidase.  相似文献   
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Cone-beam CT (CBCT) using kV imagers integrated with linear accelerators is now widely used in verifying patient position during radiation therapy. Current CBCT acquisition protocols have lowered tube current to keep the imaging dose to a minimum. This affects the usability of CBCT data sets in treatment planning by reducing the soft tissue contrast and accuracy of CT numbers (Hounsfield values). The purpose of this study is to investigate the effect of reconstruction filters on full-fan and half-fan acquisition modes of CBCT and assess the image quality parameters of contrast- to -noise ratio, spatial resolution, pixel stability and uniformity. The results of this study show the relation between the noise and resolution of a CBCT image by using different reconstruction filters and provide possible estimations of the impact of filters on image quality and subsequent optimization for image-guided radiotherapy purposes.  相似文献   
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Background

Social connection is a fundamental human need. Its absence can lead to loneliness and social isolation, adversely impacting health and well-being. Given their regular contact and trusted relationships with older people, practitioners delivering community-based primary care are well-positioned to address this issue. However, their contribution to addressing loneliness and social isolation is unclear.

Aim

This integrative review explores the contribution of the primary care workforce to interventions aimed at reducing loneliness and social isolation in community-dwelling older people.

Method

Using an integrative review method, Scopus, Web of Science, CINAHL and PubMed were searched for original research published between 2000 and 2022. Fourteen papers reporting 13 primary studies were appraised for methodological quality and included in the review. Data were extracted into a summary table and analysed using thematic analysis.

Results

Included studies came from over six countries. Internationally, primary care services have diverse structures, funding and workforces influencing their response to loneliness and social isolation. All but one intervention was multi-component, with ten studies including a group-based activity and three providing primarily individual-level activities. Only six studies reported reductions in loneliness following the intervention. Three themes were identified: characteristics of interventions; implementation context, barriers and facilitators; and differing contributions of primary care practitioners in addressing loneliness and social isolation of older people.

Conclusion

There is increasing demand and scope for primary care practitioners to assist lonely and socially isolated older people. It is important to understand how to equip and incentivise these practitioners to routinely identify, assess and respond to lonely and socially isolated older people despite varying implementation contexts. There is a need for further research that explores how the primary care team can be better utilised to deliver effective interventions that reduce the health impacts of loneliness and social isolation.  相似文献   
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