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1.
Menopause ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39042024

RESUMEN

OBJECTIVE: How women perceive menopause depends on how well they go through that period of time. However, there is no measure that can be used to assess how women perceive menopause. Therefore, we developed a valid and reliable scale (Menopause Perception Scale [MPS]) to assess how women perceive menopause. METHODS: This methodological research was conducted in three stages. First, we developed items and assessed their content validity. Second, we collected data from 470 women. Third, we assessed the scale for validity and reliability. Exploratory factor analysis and confirmatory factor analysis were used for construct validity. Cronbach's α was calculated for reliability. Pearson's correlation coefficient was used for criterion validity. Mean comparison tests were performed for known-groups validity. RESULTS: The MPS had a content validity index of 0.90. It had a Kaiser-Meier-Olkin score of 0.768, for which Bartlett's test of sphericity was significant (1,778.047; P < 0.001). The values were acceptable. The exploratory factor analysis yielded an 18-item structure with factor loads greater than 0.40. It also revealed a four-factor model (acceptance, perceived sexuality, normalization, and perceived support) confirmed by the confirmatory factor analysis. The fit indexes were acceptable. The model explained 56.64% of the total variance. The internal consistency was acceptable (Cronbach's α = 0.824). There were positive correlations between the scale and its subscales. Furthermore, the MPS was significantly correlated with the Menopause Attitude Assessment Scale (r = 0.334, P < 0.001) and the Menopause Rating Scale (r = -0.286, P < 0.001). CONCLUSIONS: The MPS is a valid, reliable, user-friendly, and practical self-report measure with satisfactory psychometric properties. Researchers should conduct cross-cultural studies to adapt it to other cultures.

2.
ACS Appl Mater Interfaces ; 15(39): 45561-45573, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37729472

RESUMEN

Surgical sutures designed to prevent infection are critical in addressing antibiotic-resistant pathogens that cause surgical site infections. Instead of antibiotics, alternative materials such as biocides have been assessed for coating commercially used sutures due to emerging antibiotic resistance concerns worldwide. This study has a new approach to the development of fibrous surgical sutures with the ability to deliver localized antibacterial agents. A new manufacturing process based on pressure spinning was used for the first time in the production of fibrous surgical sutures by physically blending antibacterial triclosan (Tri) agent with poly(lactic-co-glycolic acid) (PLGA) and poly(ethylene oxide) (PEO) polymers. Fibrous surgical sutures with virgin PLGA, virgin PEO, different ratios of PLGA-PEO, and different ratios of Tri-loaded PLGA-PEO fibrous sutures were produced to mimic the FDA- and NICE-approved PLGA-based sutures available in the market and compared for their characteristics. They were also tested simultaneously with commercially available sutures to compare their in vitro biodegradation, antibacterial, drug release, and cytotoxicity properties. After in vitro antibacterial testing for 24 h, sutures having 285 ± 12 µg/mg Tri loading were selected as a model for further testing as they exhibited antibacterial activity against all tested bacteria strains. The selected model of antibacterial fibrous sutures exhibited an initial burst of Tri release within 24 h, followed by a sustained release for the remaining time until the sutures completely degraded within 21 days. The cell viability assay showed that these surgical sutures had no cytotoxic effect on mammalian cells.


Asunto(s)
Antibacterianos , Triclosán , Animales , Antibacterianos/farmacología , Suturas , Triclosán/farmacología , Polímeros , Mamíferos
3.
Nanomedicine (Lond) ; 18(16): 1061-1073, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37610080

RESUMEN

Aims: Among solid tumors, hypoxia is a common characteristic and responsible for chemotherapeutic resistance. Hypoxia-sensitive imaging probes are therefore essential for early tumor detection, growth monitoring and drug-response evaluation. Despite significant efforts, detecting hypoxic oxygen levels remains challenging. Materials & methods: This paper demonstrates the use of an amine-rich carbon dot probe functionalized with an imidazole group that exhibits reversible fluorescence switching in normoxic and hypoxic environments. Results & conclusion: We demonstrate the ability to emit near-infrared light only under hypoxic conditions. The probes are found to be biodegradable in the presence of human digestive enzymes such as lipase. Ex vivo tissue imaging experiments revealed promising near-infrared signals even at a depth of 5 mm for the probe under ex vivo imaging conditions.


Hypoxia is the state where oxygen is not adequately available at the tissue level and is the common cause of resistance toward chemotherapeutics. Hence, probes that can detect hypoxia are important in detecting early tumor progression. Here in this paper, we have developed a fluorescent probe which helps in determining normoxic and hypoxic environments. This probe emits near-infrared light only under hypoxic conditions. The phenomena have been established herein by extensive experiments.


Asunto(s)
Colorantes Fluorescentes , Hipoxia , Humanos , Hipoxia/diagnóstico por imagen , Oxígeno , Aminas , Carbono
4.
Cell Rep ; 42(6): 112554, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37235473

RESUMEN

Intracortical microstimulation (ICMS) enables applications ranging from neuroprosthetics to causal circuit manipulations. However, the resolution, efficacy, and chronic stability of neuromodulation are often compromised by adverse tissue responses to the indwelling electrodes. Here we engineer ultraflexible stim-nanoelectronic threads (StimNETs) and demonstrate low activation threshold, high resolution, and chronically stable ICMS in awake, behaving mouse models. In vivo two-photon imaging reveals that StimNETs remain seamlessly integrated with the nervous tissue throughout chronic stimulation periods and elicit stable, focal neuronal activation at low currents of 2 µA. Importantly, StimNETs evoke longitudinally stable behavioral responses for over 8 months at a markedly low charge injection of 0.25 nC/phase. Quantified histological analyses show that chronic ICMS by StimNETs induces no neuronal degeneration or glial scarring. These results suggest that tissue-integrated electrodes provide a path for robust, long-lasting, spatially selective neuromodulation at low currents, which lessens risk of tissue damage or exacerbation of off-target side effects.


Asunto(s)
Corteza Somatosensorial , Ratones , Animales , Corteza Somatosensorial/fisiología , Electrodos , Estimulación Eléctrica/métodos , Electrodos Implantados
5.
bioRxiv ; 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36865195

RESUMEN

Intracortical microstimulation (ICMS) enables applications ranging from neuroprosthetics to causal circuit manipulations. However, the resolution, efficacy, and chronic stability of neuromodulation is often compromised by the adverse tissue responses to the indwelling electrodes. Here we engineer ultraflexible stim-Nanoelectronic Threads (StimNETs) and demonstrate low activation threshold, high resolution, and chronically stable ICMS in awake, behaving mouse models. In vivo two-photon imaging reveals that StimNETs remain seamlessly integrated with the nervous tissue throughout chronic stimulation periods and elicit stable, focal neuronal activation at low currents of 2 µA. Importantly, StimNETs evoke longitudinally stable behavioral responses for over eight months at markedly low charge injection of 0.25 nC/phase. Quantified histological analysis show that chronic ICMS by StimNETs induce no neuronal degeneration or glial scarring. These results suggest that tissue-integrated electrodes provide a path for robust, long-lasting, spatially-selective neuromodulation at low currents which lessen risks of tissue damage or exacerbation of off-target side-effects.

6.
Bioengineering (Basel) ; 10(2)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36829757

RESUMEN

Recent progress in cortical stem cell transplantation has demonstrated its potential to repair the brain. However, current transplant models have yet to demonstrate that the circuitry of transplant-derived neurons can encode useful function to the host. This is likely due to missing cell types within the grafts, abnormal proportions of cell types, abnormal cytoarchitecture, and inefficient vascularization. Here, we devised a transplant platform for testing neocortical tissue prototypes. Dissociated mouse embryonic telencephalic cells in a liquid scaffold were transplanted into aspiration-lesioned adult mouse cortices. The donor neuronal precursors differentiated into upper and deep layer neurons that exhibited synaptic puncta, projected outside of the graft to appropriate brain areas, became electrophysiologically active within one month post-transplant, and responded to visual stimuli. Interneurons and oligodendrocytes were present at normal densities in grafts. Grafts became fully vascularized by one week post-transplant and vessels in grafts were perfused with blood. With this paradigm, we could also organize cells into layers. Overall, we have provided proof of a concept for an in vivo platform that can be used for developing and testing neocortical-like tissue prototypes.

7.
J Funct Biomater ; 13(3)2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-36135571

RESUMEN

Wounds are characterised by an anatomical disruption of the skin; this leaves the body exposed to opportunistic pathogens which contribute to infections. Current wound healing bandages do little to protect against this and when they do, they can often utilise harmful additions. Historically, plant-based constituents have been extensively used for wound treatment and are proven beneficial in such environments. In this work, the essential oil of clove bud (Syzygium aromaticum) was incorporated in a polycaprolactone (PCL) solution, and 44.4% (v/v) oil-containing fibres were produced through pressurised gyration. The antimicrobial activity of these bandage-like fibres was analysed using in vitro disk diffusion and the physical fibre properties were also assessed. The work showed that advantageous fibre morphologies were achieved with diameters of 10.90 ± 4.99 µm. The clove bud oil fibres demonstrated good antimicrobial properties. They exhibited inhibition zone diameters of 30, 18, 11, and 20 mm against microbial colonies of C. albicans, E. coli, S. aureus, and S. pyogenes, respectively. These microbial species are commonly problematic in environments where the skin barrier is compromised. The outcomes of this study are thus very promising and suggest that clove bud oil is highly suitable to be applied as a natural sustainable alternative to modern medicine.

8.
Turk J Chem ; 45(5): 1432-1443, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34849057

RESUMEN

Textile azo dyes are one of the pollutants in waste water that adversely affect human and environmental health. Removal of these chemicals from wastewater is important for eco-system and human health. In this study, Bi2O3 nanoflakes and ZnO were synthesized by the co-precipitation method. Adsorption and photocatalytic degradation reactions were carried out to remove dyes (Victoria blue (VB) and Malachite green (MG)) from wastewater with the photocatalysts. In order to improve the activity of catalysts, cetyltrimethylammoniumbromide (CTAB) was added as a surfactant to pure oxide structures, and Bi2O3-CTAB and ZnO-CTAB catalysts were prepared. The structural and morphological properties of these catalysts were determined by BET, XRD, DRS, FTIR, and SEM analysis. It was found that the activity of the catalyst was improved by adding surfactant to the Bi2O3. The total mineralization of VB dye was completed in 60 min under sunlight with Bi2O3-CTAB catalyst. However, the degradation of the MG dye with the same catalyst under UV-C irradiation could be completed in 120 min.

9.
Commun Biol ; 4(1): 846, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34267305

RESUMEN

Dental plaques are biofilms that cause dental caries by demineralization with acidogenic bacteria. These bacteria reside inside a protective sheath which makes any curative treatment challenging. We propose an antibiotic-free strategy to disrupt the biofilm by engineered clustered carbon dot nanoparticles that function in the acidic environment of the biofilms. In vitro and ex vivo studies on the mature biofilms of Streptococcus mutans revealed >90% biofilm inhibition associated with the contact-mediated interaction of nanoparticles with the bacterial membrane, excessive reactive oxygen species generation, and DNA fragmentation. An in vivo examination showed that these nanoparticles could effectively suppress the growth of S. mutans. Importantly, 16S rRNA analysis of the dental microbiota showed that the diversity and richness of bacterial species did not substantially change with nanoparticle treatment. Overall, this study presents a safe and effective approach to decrease the dental biofilm formation without disrupting the ecological balance of the oral cavity.


Asunto(s)
Biopelículas/efectos de los fármacos , Microbiota/fisiología , Nanopartículas/toxicidad , Polímeros/toxicidad , Streptococcus mutans/efectos de los fármacos , Animales , Antibacterianos/farmacología , Biopelículas/crecimiento & desarrollo , Femenino , Humanos , Ratones , Viabilidad Microbiana/efectos de los fármacos , Microbiota/genética , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Células 3T3 NIH , Nanopartículas/química , Nanopartículas/ultraestructura , Polímeros/química , ARN Ribosómico 16S/genética , Ratas Sprague-Dawley , Streptococcus mutans/crecimiento & desarrollo , Streptococcus mutans/ultraestructura
10.
J Pak Med Assoc ; 71(3): 843-848, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34057933

RESUMEN

OBJECTIVE: To determine perception levels of student nurses about nursing diagnosis. METHODS: The descriptive, comparative, cross-sectional study was conducted at the Nursing Department, Faculty of Health Sciences, Karadeniz Technical University, Trabzon, Turkey, in December 2015, and comprised nursing students studying in the 2nd, 3rd and 4th grades. Data was collected using a personal information form and the Perceptions of Nursing Diagnosis Survey. Data was analysed using SPSS 18. RESULTS: Of the 386 students, 317(82%) were female and 321(83%) considered themselves competent enough to make diagnosis. Also, 268(69%) students thought that nursing diagnosis was useful in providing planned, correct and systemised diagnosis. Mean total score of perception of nursing diagnosis of female students was higher than males (p=0.005). CONCLUSIONS: The students' perception level of nursing diagnosis was positive.


Asunto(s)
Enfermeras y Enfermeros , Estudiantes de Enfermería , Estudios Transversales , Femenino , Humanos , Masculino , Diagnóstico de Enfermería , Percepción , Turquía
11.
Pharmaceutics ; 13(5)2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33922739

RESUMEN

This study investigates the usage of electrohydrodynamic (EHD)-3D printing for the fabrication of bacterial cellulose (BC)/polycaprolactone (PCL) patches loaded with different antibiotics (amoxicillin (AMX), ampicillin (AMP), and kanamycin (KAN)) for transdermal delivery. The composite patches demonstrated facilitated drug loading and encapsulation efficiency of drugs along with extended drug release profiles. Release curves were also subjected to model fitting, and it was found that drug release was optimally adapted to the Higuchi square root model for each drug. They performed a time-dependent and diffusion-controlled release from the patches and followed Fick's diffusion law by the Korsmeyer-Peppas energy law equation. Moreover, produced patches demonstrated excellent antimicrobial activity against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) strains, so they could be helpful in the treatment of chronic infectious lesions during wound closures. As different tests have confirmed, various types of antibiotics could be loaded and successfully released regardless of their types from produced BC/PCL patches. This study could breathe life into the production of antibiotic patches for local transdermal applications in wound dressing studies and improve the quality of life of patients.

12.
J R Soc Interface ; 18(174): 20200798, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33402019

RESUMEN

The recently emerged coronavirus pandemic (COVID-19) has become a worldwide threat affecting millions of people, causing respiratory system related problems that can end up with extremely serious consequences. As the infection rate rises significantly and this is followed by a dramatic increase in mortality, the whole world is struggling to accommodate change and is trying to adapt to new conditions. While a significant amount of effort is focused on developing a vaccine in order to make a game-changing anti-COVID-19 breakthrough, novel coronavirus (SARS-CoV-2) is also developing mutations rapidly as it transmits just like any other virus and there is always a substantial chance of the invented antibodies becoming ineffective as a function of time, thus failing to inhibit virus-to-cell binding efficiency as the spiked protein keeps evolving. Hence, controlling the transmission of the virus is crucial. Therefore, this review summarizes the viability of coronaviruses on inanimate surfaces under different conditions while addressing the current state of known chemical disinfectants for deactivation of the coronaviruses. The review attempts to bring together a wide spectrum of surface-virus-cleaning agent interactions to help identify material selection for inanimate surfaces that have frequent human contact and cleaning procedures for effective prevention of COVID-19 transmission.


Asunto(s)
COVID-19/virología , Desinfectantes/farmacología , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/fisiología , COVID-19/prevención & control , Desinfección , Humanos , Propiedades de Superficie
13.
Polymers (Basel) ; 11(7)2019 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-31277438

RESUMEN

Bacterial Cellulose (BC) has over recent decades shown great versatility in wound healing dressings, but is difficult to spin fibers with at high concentrations. An investigation into the preparation of bandage-like fibrous meshes is carried out to determine the optimal blend of polycaprolactone (PCL) and polylactic acid (PLA) as a suitable carrier for BC. Using a simple centrifugal spinning setup, polymer blends of PCL, PLA and BC are investigated as a ternary system to determine the most suitable composition with a focus on achieving maximal BC concentration. It is found that BC content in the fibers above 10 wt % reduced product yield. By creating blends of PLA-PCL fibers, we can create a more suitable system in terms of yield and mechanical properties. The fibrous samples are examined for yield, fiber morphology using scanning electron microscopy, mechanical properties using tensile testing and chemical characteristics using Fourier-transform infrared spectroscopy. A fibrous scaffold with > 30 wt % BC was produced with enhanced mechanical properties owing to the blending of PLA and PCL.

14.
Int Wound J ; 16(3): 730-736, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30767437

RESUMEN

Cinnamon-containing polycaprolactone (PCL) bandages were produced by pressurised gyration and their anti-fungal activities against Candida albicans were investigated. It was found that by preparing and spinning polymer solutions of cinnamon with PCL, fibres capable of inhibiting fungal growth could be produced, as observed in disk diffusion tests for anti-fungal susceptibility. Fascinatingly, compared with raw cinnamon powder, the novel cinnamon-loaded fibres had outstanding long-term activity. The results presented here are very promising and may indeed accelerate a new era of using completely natural materials in biomedical applications, especially in wound healing.


Asunto(s)
Antifúngicos/química , Vendajes , Candida albicans/efectos de los fármacos , Cinnamomum zeylanicum/química , Extractos Vegetales/química , Poliésteres/química
15.
IEEE Trans Nanobioscience ; 17(3): 321-328, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29994218

RESUMEN

Biocompatible nanocomposite electrospun fibers containing Polyurethane/Chitosan/ $\beta $ -Tri calcium phosphate with diverse concentrations were designed and produced through the electrospinning process for bone tissue engineering applications. After the production process, density measurement, viscosity, electrical conductivity, and tensile strength measurement tests were carried out as physical analyses of blended solutions. The chemical structural characterization was scrutinized using Fourier transform infrared spectrometer (FTIR), and scanning electron microscopy (SEM) was used to observe the morphological details of developed electrospun scaffolds. Cell viability, attachment, and proliferation were performed using a L929 fibroblast cell line. Based on the physical, SEM, FTIR analysis, and cell culture studies, preferable nanofiber composition was selected for further studies. Amoxicillin (AMX) was loaded to that selected nanofiber composition for examination of the drug release. In comparison with other studies on similar AMX controlled products, higher drug loading and encapsulation efficiencies were obtained. It has been clearly found that the developed nanofiber composites have potential for bone tissue engineering applications.


Asunto(s)
Amoxicilina/química , Huesos , Poliuretanos/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Huesos/citología , Huesos/fisiología , Fosfatos de Calcio/química , Línea Celular , Quitosano/química , Técnicas Electroquímicas/métodos , Ratones
16.
Int Wound J ; 15(5): 789-797, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29806201

RESUMEN

Electrospun nanofibrous scaffolds are promising regenerative wound dressing options but have yet to be widely used in practice. The challenge is that nanofibre productions rely on bench-top apparatuses, and the delicate product integrity is hard to preserve before reaching the point of need. Timing is critically important to wound healing. The purpose of this investigation is to produce novel nanofibrous scaffolds using a portable, hand-held "gun", which enables production at the wound site in a time-dependent fashion, thereby preserving product integrity. We select bacterial cellulose, a natural hydrophilic biopolymer, and polycaprolactone, a synthetic hydrophobic polymer, to generate composite nanofibres that can tune the scaffold hydrophilicity, which strongly affects cell proliferation. Composite scaffolds made of 8 different ratios of bacterial cellulose and polycaprolactone were successfully electrospun. The morphological features and cell-scaffold interactions were analysed using scanning electron microscopy. The biocompatibility was studied using Saos-2 cell viability test. The scaffolds were found to show good biocompatibility and allow different proliferation rates that varied with the composition of the scaffolds. A nanofibrous dressing that can be accurately moulded and standardised via the portable technique is advantageous for wound healing in practicality and in its consistency through mass production.


Asunto(s)
Vendajes , Celulosa/uso terapéutico , Nanofibras/uso terapéutico , Poliésteres/uso terapéutico , Ingeniería de Tejidos/instrumentación , Ingeniería de Tejidos/métodos , Andamios del Tejido , Adulto , Anciano , Anciano de 80 o más Años , Proliferación Celular/fisiología , Supervivencia Celular/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cicatrización de Heridas/fisiología
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