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1.
Curr Issues Mol Biol ; 45(5): 4181-4199, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37232735

RESUMO

Chronic exposure to ultraviolet (UV) radiation is a major cause of photoaging. It involves extrinsic aging, wrinkle formation, and skin dehydration, and leads to excessive production of active oxygen that adversely affects the skin. Here, we investigated the antiphotoaging effect of AGEs BlockerTM (AB), which comprises Korean mint aerial part and fig and goji berry fruits. Compared to its individual components, AB was more potent at increasing the expression of collagen and hyaluronic acid and decreasing MMP-1 expression in UVB-irradiated Hs68 fibroblasts and HaCaT keratinocytes. In Skh:HR-1 hairless mice exposed to 60 mJ/cm2 UVB for 12 weeks, oral administration of 20 or 200 mg/kg/day AB restored skin moisture by improving UVB-induced erythema, skin moisture, and transepidermal water loss, and alleviated photoaging by improving UVB-induced elasticity and wrinkles. Moreover, AB upregulated the mRNA levels of hyaluronic acid synthase and collagen-related Col1a1, Col3a1, and Col4a1 genes, increasing hyaluronic acid and collagen expression, respectively. AB inhibited UVB-induced MAPK and AP-1 (c-fos) activation, resulting in significantly downregulated expression of MMP-1 and -9, which are responsible for collagen degradation. AB also stimulated the expression and activity of antioxidative enzymes and reduced lipid peroxidation. Thus, AB is a potential preventive and therapeutic agent for photoaging.

2.
Curr Issues Mol Biol ; 44(12): 6280-6289, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36547089

RESUMO

Hair loss is an important problem affecting the quality of life in modern society. Recent studies show that Annurca apple extract (AAE), enriched in procyanidin B2 and nutraceuticals, promotes hair growth and induces keratin production. In this study, we investigated the effects of AAE by orally administering AAE in six-week-old C57BL/6 mice once a day for 21 d. We observed improvement in hair length, thickness, weight, and density. The gene expression of two growth factors related to hair growth, vascular endothelial growth factor A (VEGFA) and fibroblast growth factor 7 (FGF-7), were measured using the quantitative reverse transcription polymerase chain reaction (qRT-PCR). The gene expression of both VEGFA and FGF-7 increased significantly in the AAE-treated group. Additionally, treatment with AAE suppressed the gene expression of type 1 5α-reductase. Histological analysis showed that protein levels of cytokeratin 5 and 10 were increased in the skin tissues of the AAE-treated group. These results suggest that AAE might be a potential therapeutic natural product that prevents hair loss by promoting the expression of hair growth-related factors.

3.
Sensors (Basel) ; 21(5)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668260

RESUMO

We present a back-to-back (BTB) structured, dual-mode ultrasonic device that incorporates a single-element 5.3 MHz transducer for high-intensity focused ultrasound (HIFU) treatment and a single-element 20.0 MHz transducer for high-resolution ultrasound imaging. Ultrasound image-guided surgical systems have been developed for lesion monitoring to ensure that ultrasonic treatment is correctly administered at the right locations. In this study, we developed a dual-element transducer composed of two elements that share the same housing but work independently with a BTB structure, enabling a mode change between therapy and imaging via 180-degree mechanical rotation. The optic fibers were embedded in the HIFU focal region of ex vivo chicken breasts and the temperature change was measured. Images were obtained in vivo mice before and after treatment and compared to identify the treated region. We successfully acquired B-mode and C-scan images that display the hyperechoic region indicating coagulation necrosis in the HIFU-treated volume up to a depth of 10 mm. The compact BTB dual-mode ultrasonic transducer may be used for subcutaneous thermal ablation and monitoring, minimally invasive surgery, and other clinical applications, all with ultrasound only.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Ultrassom , Animais , Camundongos , Transdutores , Ultrassonografia
4.
Healthcare (Basel) ; 12(3)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38338279

RESUMO

This study aimed to develop and validate a scale for measuring the therapeutic communication of nursing students. The scale development and evaluation study was conducted based on the scale development guidelines of DeVellis. A 47-item instrument was developed based on a review of the literature and interviews with 16 experts. Content validity was evaluated by ten nursing scholars, and the number of items was reduced to 35. The scale was administered to 352 nursing students from three regions in South Korea in 2022. Exploratory factor analysis and confirmatory factor analysis were performed on the scale items. Convergent validity, discriminant validity, and internal consistency reliability of the scale were evaluated. The factor analysis resulted in 15 items and two factors: relationship building and problem solving. Confirmatory factor analysis and evaluation of convergent and discriminant validity provided support for the validity of the two-factor Therapeutic Communication Scale in nursing students. The total scale demonstrated good internal consistency, with a McDonald's omega (ω) of 0.89. The Therapeutic Communication Scale is a reliable and valid measure that can be used to assess nursing students' therapeutic communication competence related to patient-centered nursing and provide foundational data to improve such skills.

5.
IEEE Trans Ultrason Ferroelectr Freq Control ; 71(10): 1269-1288, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39250365

RESUMO

Acoustic tweezers have attracted attention in various fields of cell biology, including in vitro single-cell and intercellular mechanics. Compared with other tweezing technologies such as optical and magnetic tweezers, acoustic tweezers possess stronger forces and are safer for use in biological systems. However, due to the limited spatial resolution or limited size of target objects, acoustic tweezers have primarily been used to manipulate cells in vitro. To extend the advantages of acoustic tweezers to other levels (e.g., molecular and in vivo levels), researchers have recently developed various types of acoustic tweezers such as single-beam acoustic tweezers (SBATs), surface acoustic wave (SAW) tweezers, and acoustic-streaming tweezers. Among these, SBATs utilize a single-focused beam, making the transducer and system simple, noninvasive, and capable of producing strong forces compared with other types of tweezers. Depending on the acoustic beam pattern, SBATs can be classified into Rayleigh regime, Mie regime, and acoustic vortex with different trapping dynamics and application levels. In this review, we provide an overview of the principles and configuration of each type of SBAT, their applications ranging from molecular to in vivo studies, and their limitations and prospects. Thus, this review demonstrates the significance and potential of SBAT technology in biophysics and biomedical engineering.


Assuntos
Acústica , Animais , Desenho de Equipamento , Humanos , Biologia Celular/instrumentação , Pinças Ópticas , Micromanipulação/instrumentação , Micromanipulação/métodos
6.
iScience ; 26(11): 108178, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37915606

RESUMO

Acoustic tweezers (ATs) are a promising technology that can trap and manipulate microparticles or cells with the focused ultrasound beam without physical contact. Unlike optical tweezers, ATs may be used for in vivo studies because they can manipulate cells through tissues. However, in previous non-invasive microparticle trapping studies, ATs could only trap spherical particles, such as beads. Here, we present a theoretical analysis of how the acoustic beam traps red blood cells (RBCs) with experimental demonstration. The proposed modeling shows that the trapping of a non-spherical, biconcave-shaped RBC could be successfully done by single-beam acoustic tweezers (SBATs). We demonstrate this by trapping RBCs using SBATs in the Rayleigh regime, where the cell size is smaller than the wavelength of the beam. Suggested SBAT is a promising tool for cell transportation and sorting.

7.
Biomed Opt Express ; 14(1): 89-105, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36698663

RESUMO

Photoacoustic (PA) imaging is a high-fidelity biomedical imaging technique based on the principle of molecular-specific optical absorption of biological tissue constitute. Because PA imaging shares the same basic principle as that of ultrasound (US) imaging, the use of PA/US dual-modal imaging can be achieved using a single system. However, because PA imaging is limited to a shallower depth than US imaging due to the optical extinction in biological tissue, the PA signal yields a lower signal-to-noise ratio (SNR) than US images. To selectively amplify the PA signal, we propose a switchable preamplifier for acoustic-resolution PA microscopy implemented on an application-specific integrated circuit. Using the preamplifier, we measured the increments in the SNR with both carbon lead and wire phantoms. Furthermore, in vivo whole-body PA/US imaging of a mouse with a preamplifier showed enhancement of SNR in deep tissues, unveiling deeply located organs and vascular networks. By selectively amplifying the PA signal range to a level similar to that of the US signal without contrast agent administration, our switchable amplifier strengthens the mutual complement between PA/US imaging. PA/US imaging is impending toward clinical translation, and we anticipate that this study will help mitigate the imbalance of image depth between the two imaging modalities.

8.
Food Sci Biotechnol ; 32(5): 713-721, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37009046

RESUMO

This study was conducted to develop a selective medium for enumerating LAB and Bifidobacteria in food samples. Thirteen media were evaluated to determine their suitability for selectively enumerating LAB (17 bacilli and 7 cocci) and Bifidobacteria (12 strains) under aerobic and anaerobic conditions. When BL, BCP, and mMRS were supplemented with propionic acid (5 ml/l) and adjusted to pH 5, the growth of all indicator microorganisms was inhibited; however, these media also inhibited the growth of certain LAB and Bifidobacterial strains. Using propionic acid, the pH levels of BL, BCP, and mMRS were adjusted to pH 5.2, 6.0, and 6.0, respectively. These media inhibited the growth of all indicator microorganisms, whereas they did not inhibit any of the LAB and Bifidobacteria strains under anaerobic conditions. Overall, BLP (pH 5.8) lacking blood showed significantly higher bacterial counts compared with other media in food products. Further analyses indicated that BLP (pH 5.8) was the most suitable medium for enumerating LAB and Bifidobacteria in food. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01202-z.

9.
Ultrason Sonochem ; 82: 105844, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34965507

RESUMO

Microbubbles are widely used in medical ultrasound imaging and drug delivery. Many studies have attempted to quantify the collapse pressure of microbubbles using methods that vary depending on the type and population of bubbles and the frequency band of the ultrasound. However, accurate measurement of collapse pressure is difficult as a result of non-acoustic pressure factors generated by physical and chemical reactions such as dissolution, cavitation, and interaction between bubbles. In this study, we developed a method for accurately measuring collapse pressure using only ultrasound pulse acoustic pressure. Under the proposed method, the collapse pressure of a single hollow glass microsphere (HGM) is measured using a high-frequency (20-40 MHz) single-beam acoustic tweezer (SBAT), thereby eliminating the influence of additional factors. Based on these measurements, the collapse pressure is derived as a function of the HGM size using the microspheres' true density. We also developed a method for estimating high-frequency acoustic pressure, whose measurement using current hydrophone equipment is complicated by limitations in the size of the active aperture. By recording the transmit voltage at the moment of collapse and referencing it against the corresponding pressure, it is possible to estimate the acoustic pressure at the given transmit condition. These results of this study suggest a method for quantifying high-frequency acoustic pressure, provide a potential reference for the characterization of bubble collapse pressure, and demonstrate the potential use of acoustic tweezers as a tool for measuring the elastic properties of particles/cells.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35377844

RESUMO

Current miniaturized ultrasound transducers suffer from insufficient attenuation from the backing layer due to their limited thickness. The thickness of the backing layer is one of the critical factors determining the device size and transducer performance for miniaturized transducers inserted and operated in a limited space. Glass bubbles, polyamide resin, and tungsten powder are combined to form a new highly attenuative backing material. It has high attenuation (>160 dB/cm at 5 MHz), which is five times greater than silver-based conductive epoxy commonly used for high-frequency ultrasound transducers, appropriate acoustic impedance (4.6 MRayl), and acceptable damping capability. An intravascular ultrasound (IVUS) transducer constructed with the 170 [Formula: see text] of the proposed backing layer demonstrated that the amplitude of the signal returned from the backing layer was 1.8 times smaller, with ring-down attenuated by 6 dB. Wire-phantom imaging revealed that the axial resolution was 30% better with the suggested backing than silver-based conductive epoxy backing. Because of its excellent attenuation capability even at a limited thickness, simple manufacturing process, and easy customization capability, the suggested highly attenuative backing layer may be used for miniaturized ultrasound transducers.


Assuntos
Prata , Transdutores , Desenho de Equipamento , Imagens de Fantasmas , Ultrassonografia/métodos
11.
Front Sports Act Living ; 3: 728749, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712952

RESUMO

With virtual reality (VR) video game users beginning to see beta advertisements within game play, this conceptual article adds a needed digital and interactive marketing research foundation to the new construct of VR in-game advertising (IGA) activation. New consumer VR technology continues to disrupt traditional media as a $7.7 billion USD industry, that is expected to reach $57.55 billion by 2027. As such, marketing researchers must continue to evolve and understand the interdisciplinary VR research evolution as many VR users are likely to view IGA as intrusive. IGA and VR are not new constructs, but IGA within VR is unique as VR consumers have not yet experienced VR IGA intrusion. This article utilizes a sport marketing focus to provide an industry specific set of examples for the reader, however this article can be applied to broader fields including communications and interactive marketing. The main contributions of this article are 2-fold. First the development of a VR In-Game Advertising Congruity Framework is developed through a review of the literature and application to VR IGA in the topical areas of congruity of the IGA, interactivity of the IGA, intrusiveness of the IGA, realism of the experience, telepresence, brand awareness, and attitude toward the IGA. Secondly, a proper VR context definition of telepresence is provided through review of the literature that takes into account the interaction of a VR participant. This article aims to aid marketers in making informed IGA development decisions through strategic choice, via a centralized VR IGA congruity framework, that not only enhances brand awareness, but leaves participants with a favorable attitude toward the IGA to increase sales activation.

12.
Korean J Food Sci Anim Resour ; 34(1): 26-32, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26760742

RESUMO

This study was conducted to examine the effects of eggshell membrane hydrolysates (ESMH) on the anti-inflammatory, anti-wrinkle, anti-microbial activity, and moisture-protection for cosmetic use. Whole ESMH (before fractionation), and fraction I (>10 kDa), fraction II (3-10 kDa), and fraction III (<3 kDa) of the hydrolysates were assessed in this experiment. As lipopolysaccharide (LPS) and IFN-γ caused the inflammation on Raw264.7 cell, whole ESMH and fraction I showed to be effective in inhibiting the induction of cell inflammation depending on the concentration, and also showed outstanding effect to suppress the skin inflammation. Fraction I inhibited collagenase and elastase activities to a greater extent than the other fractions, while all fractions had antibiotic effects at concentrations of 10 mg/disc and 20 mg/disc. In addition, it showed the moisture protection effects of skin on the holding amount and losing amount of moisture in upper-inner arm of the human body with a relatively low loss rate in skin, which confirmed that the hydrolyzed fractions of ESM helps to form the superior protective layer of moisture. It was concluded that ESMH fractions with different molecular weights, especially the 10 kDa fraction, have anti-lipopolysaccharide, anti-IFN-γ-induced inflammation, anti- collagenase and elastase activities, and thus can be used as a cosmetic agent to protect skin.

13.
Hip Pelvis ; 26(2): 107-14, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27536567

RESUMO

PURPOSE: To evaluate the factors affecting the bone union time and the occurrence of nonunion after intramedullary nailing of subtrochanteric femoral fractures in adults. MATERIALS AND METHODS: We retrospectively reviewed data from 31 patients (22 men and 9 women) who had undergone femoral intramedullary nailing at least 1 year post-operatively and analyzed the bone union time, nonunion rates, and factors that affected the bone union time according to the fracture classification (AO and Fielding classifications), comminution of the medial cortex, reduction method, and additional cerclage wiring. RESULTS: The average union time was 26.4 weeks. There were no differences in the bone union time according to the fracture classification, reduction method, or additional cerclage wiring. Significant differences were found in the bone union time between the medial cortex comminution and non-comminution groups. A relatively strong positive correlation was detected between the degree of post-operative displacement and the bone union time. Nonunion occurred in three cases and there was no failure of implants. CONCLUSION: The bone union time was not affected by the reduction method nor additional cerclage wiring in intramedullary nailing of subtrochanteric femur fractures. Comminution of the medial cortex and the degree of the postoperative displacement of fractures contributed to the delayed time of union.

14.
Int J Food Microbiol ; 189: 67-74, 2014 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-25126968

RESUMO

This study was conducted to develop a selective medium for the detection of Campylobacter spp. in fresh produce. Campylobacter spp. (n=4), non-Campylobacter (showing positive results on Campylobacter selective agar) strains (n=49) isolated from fresh produce, indicator bacteria (n=13), and spoilage bacteria isolated from fresh produce (n=15) were plated on four Campylobacter selective media. Bolton agar and modified charcoal cefoperazone deoxycholate agar (mCCDA) exhibited higher sensitivity for Campylobacter spp. than did Preston agar and Hunt agar, although certain non-Campylobacter strains isolated from fresh produce by using a selective agar isolation method, were still able to grow on Bolton agar and mCCDA. To inhibit the growth of non-Campylobacter strains, Bolton agar and mCCDA were supplemented with 5 antibiotics (rifampicin, polymyxin B, sodium metabisulfite, sodium pyruvate, ferrous sulfate) and the growth of Campylobacter spp. (n=7) and non-Campylobacter strains (n=44) was evaluated. Although Bolton agar supplemented with rifampicin (BR agar) exhibited a higher selectivity for Campylobacter spp. than did mCCDA supplemented with antibiotics, certain non-Campylobacter strains were still able to grow on BR agar (18.8%). When BR agar with various concentrations of sulfamethoxazole-trimethoprim were tested with Campylobacter spp. (n=8) and non-Campylobacter (n=7), sulfamethoxazole-trimethoprim was inhibitory against 3 of 7 non-Campylobacter strains. Finally, we validated the use of BR agar containing 50mg/L sulfamethoxazole (BRS agar) or 0.5mg/L ciprofloxacin (BRCS agar) and other selective agars for the detection of Campylobacter spp. in chicken and fresh produce. All chicken samples were positive for Campylobacter spp. when tested on mCCDA, BR agar, and BRS agar. In fresh produce samples, BRS agar exhibited the highest selectivity for Campylobacter spp., demonstrating its suitability for the detection of Campylobacter spp. in fresh produce.


Assuntos
Ágar/química , Campylobacter/isolamento & purificação , Meios de Cultura/química , Carne/microbiologia , Verduras/microbiologia , Animais , Antibacterianos/farmacologia , Campylobacter/efeitos dos fármacos , Campylobacter/crescimento & desenvolvimento , Bovinos , Galinhas , Cavalos , Suínos
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