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The main objective of this study was to prepare functional allopurinol (ALP) incorporated biomaterials using mungbean starch, polyvinyl alcohol, melanin (MEL), and plasticizers. Prepared biomaterials were characterized by FE-SEM and FT-IR analysis. Photothermal conversion efficiencies and ALP release properties of biomaterials were evaluated with NIR laser irradiation. When biomaterials were irradiated with the NIR laser, temperatures increase of MEL-added biomaterials were higher than those of MEL-non-added biomaterials. After NIR laser irradiation, ALP release rates of MEL-added biomaterials were 1.62 times faster than those of MEL-non-added biomaterials. In addition, ALP release using an artificial skin was increased by NIR laser irradiation. ALP release from biomaterials followed Fickian diffusion mechanism, while ALP release using an artificial skin followed a non-Fickian diffusion mechanism. Xanthine oxidase inhibitory (%) for MEL-added biomaterials with/without the addition of GL and XL were 47.5%, 61.7%, and 65.1%, respectively.

CRISPR/Cas9 and CRISPR/Cas12a are characterized by a single-component effector protein. Despite unique features like DNA cleavage with 5′ staggered ends and a single crRNA, Cas12a has not been adopted in therapeutics to the same extent as Cas9. To address the pressing therapeutic needs for effective CRISPR/Cas12 systems, we selected two candidates, designated mgCas12a-1 and mgCas12a-2, from an analysis of the human microbiome metagenome (mg) for biochemical characterization. These new Cas12 proteins shared about 37% identity with FnCas12a from Francisella novicida and showed preference for Mn2+ and Mg2+ over Ca2+ or Fe2+ as divalent metal ions. The new Cas12 proteins also tolerated pH values from 5 to 8 and temperatures from 30°C to 50°C and had lower non-specific nuclease activity upon prolonged incubation than did FnCas12a. Considering their biochemical characteristics and greater purification yield, the novel mgCas12a proteins may expedite the application of Cas12a proteins in genomics research as well as human therapeutics.

Gastric inverted polyps (GIPs) are rare gastric polyps characterized by a submucosal inverted growth of mucosal components. Because of their rarity, they are not well characterized and are diagnostically challenging. We examined 12 cases of GIPs arising in 8 male and 4 female patients (mean age: 56 y). Most GIPs (11/12, 92%) occurred as a single, rounded subepithelial lesion in the body or fundus (mean size: 14.9 mm). Histologically, GIPs consisted of gastric-type glandular epithelium and smooth muscle component, growing in an endophytic manner; however, they displayed significant morphologic variations. We classified GIPs into 3 subtypes by the following features: communication with the mucosal surface, smooth muscle boundary, and tissue organization. The defining characteristics of type 1 were a mucosal communicating structure at the center and a well-defined smooth muscle boundary, resulting in a characteristic low-magnification morphology of a round vase. Type 2 had an organized glandular proliferation with smooth muscle boundary and no central communicating structure. Type 3 GIPs had no mucosal communicating structure or smooth muscle boundary; its key histologic feature was the lobular organization pattern produced by proliferations of cystic or hyperplastic glands and smooth muscle. All type 1 GIPs exhibited coexisting adenocarcinoma (3 cases) or stromal proliferation (3 cases). Three patients with type 2 GIP had separate adenocarcinoma. None of the type 3 GIPs had accompanying carcinoma. In conclusion, GIPs are a heterogenous group showing different morphology and clinical behavior. Notably, type 1 GIP could be considered a precancerous lesion with the potential to develop adenocarcinoma.

Melanotic oncocytic metaplasia (MOM) in the nasopharyngeal space is a very rare entity. Only 35 cases have been reported in the English literature, and most patients were East Asian males between 60 and 70 years of age. MOM presents as a brown or black lesion with slight elevation of the mucosa. These lesions are benign and defined as cellular enlargement with eosinophilic granular melanin-pigmented cytoplasm caused by mitochondrial accumulation. However, such presentation can lead physicians to misjudge MOM as a malignant lesion. Recently, we experienced a case of MOM of the nasopharynx. A 58-year-old woman was admitted to the internal medicine department with small-volume hemoptysis and referred to the ENT department for evaluation. She was a regular smoker without any medical history. Sinus endoscopy showed black pigmented lesions on both the torus tubaris and left posterior tonsillar pillar, with low bleeding risk. Excisional biopsy of the lesion was performed, and oncocytic metaplasia was confirmed pathologically. Hemoptysis showed spontaneous remission and no recurrence or other symptoms over 12 months of follow up. Melanotic oncocytic metaplasia in the nasopharynx should be clinically recognized to avoid misdiagnosis as a malignancy like melanoma.

Thermoplastic elastomer from ethylene vinyl acetate (EVA) was blended with a biodegradable polymer, poly(lactic acid) (PLA), to develop ecofriendly EVA/PLA foams. The thermal and mechanical propert...

Diffuse involvement of colorectal lymphoma masquerading as colitis is a very rare presentation of primary colorectal lymphoma. Detecting occult lymphoma is difficult in the setting of diffuse colonic involvement with no definite mass and inflammatory mucosal changes. We encountered a case of diffuse-type primary colorectal lymphoma simulating ulcerative colitis in a previously healthy 31-year-old woman. Despite multiple mucosal biopsies, the biopsy diagnosis was not made due to unawareness of atypical lymphocytes admixed with dense lymphoplasmacytic infiltration. The present case emphasizes the importance of being aware of this rare presentation of primary colorectal lymphoma in order to avoid misdiagnosis.

Polymeric humidity sensors have been widely studied because of their advantages in terms of low cost, simple preparation, and easy process. Most of those researches focused on the improvement in the humidity sensing performance by adding other materials. However, it is also important to understand the correlation between the polymer property and sensing characteristics. In this study, polyethylene oxide (PEO) of various molecular weights was used for the humidity sensing material and prepared by electrospinning. The morphological change and electrochemical properties of the humidity active layer were investigated to demonstrate the effect of the molecular weight on the sensing performance, including the sensitivity and linearity of electrical impedance variation, response and recovery time, and moisture stability. The humidity sensor having the highest molecular weight presented the best sensitivity and linearity of the impedance change in the specific humidity range over 67% because it was composed of complete nanofibers and showed good electrochemical property. In addition, the fastest response and recovery time, least hysteresis, and excellent moisture stability were achieved by the high surface area and connectivity of the nanofibers.

Background Primary renal well-differentiated neuroendocrine tumors (WDNETs) also called carcinoid and atypical carcinoid are extremely rare, and little is known about parameters that may predict prognosis at diagnosis. Methods Six cases of primary renal WDNET were collected. After reviewing slides stained with hematoxylin and eosin, proportions of each growth pattern were determined. Synaptophysin, chromogranin, CD56, and Ki-67 immunostaining and Ki-67 morphometric analysis were performed. Results Patients included three female and three males, mean age was 53.3 years. The mean tumor size was 4.5 cm, three cases were greater than 5 cm. At the time of initial surgery, lymph node and/or distant metastasis was confirmed in two cases. In a third case, no metastasis was initially found, but lymph node metastasis was identified during follow-up. The remaining three cases did not exhibit metastasis. Histopathologically, the renal WDNETs were primarily composed of ribbon-like and sheet-like growth patterns. Most of the tumors were diffusely positive for neuroendocrine markers. Mitotic count was high (≥2/10HPF) in cases with lymph node or distant metastasis but was low (

An electro-conductive para-aramid knit was manufactured by a dip-coating in a graphene/waterborne polyurethane(WPU) composite for confirming to use as a fabric heating element applicable to a protective clothing requiring durability. The para-aramid knit was dipped in 8 wt% graphene/WPU composite solution up to five-coat cycles. As a result of electro-conductive textile by number of dip-coating cycles, the electrical, and specifically electrical heating performances were increased number of cycles from one to five. The sample with the best electrical and electrical heating performance was the five-coat sample, and to improve those properties it was hot-pressed at 100 °C, 120 °C, 140 °C and 160 °C. After hot pressing, the entire surface of the sample was filled with graphene/WPU composite and indicated smoothly surface, thus the electrical and electrical heating performance was improved than the five-coat sample. The best performance of was indicated hot-pressed at 140 °C, with a surface resistivity and capacitance of 7.5 × 104 Ω/sq and 89.4 pF, respectively. When a voltage of 50 V was applied, the surface temperature reached 54.8 °C. The five-coat sample with hot-pressed at 140 °C could be applied to a heat-resistant para-aramid knit glove with the touch screen of a mobile phone and electric heating performance.

This study focuses on the synthesis of functional allopurinol (ALP) imprinted biomaterials for a transdermal drug delivery using mung bean starch (MBS), polyvinyl alcohol (PVA), sodium benzoate (SB) as a crosslinking agent, and poloxamer (PX) as a thermo-sensitive polymer. Prepared functional biomaterials were characterized and evaluated by SEM, FT-IR analysis, and physical properties. Results of ALP recognition properties indicated that adsorbed amounts (Q) of ALP on functional ALP imprinted biomaterials were 3.8 to 4.9-fold higher than that of non-ALP imprinted biomaterial. Results of ALP release revealed that the ALP release rate for PX added biomaterials was 1.10 (36.5 °C) or 1.30 (45 °C) times faster than that at 25 °C. These results indicate that functional ALP imprinted biomaterials have thermo-sensitive properties due to the addition of PX. Results of ALP release using artificial skin indicated that ALP release was increased at a relatively steady-state rate for 3 h and that the ALP release behavior followed the non-Fickian diffusion mechanism.

This study investigated the thermal insulation properties based on electrical heating test of graphene-based multi-layer fabric heating elements to confirm the possibility of application for fabric heating element for protective clothing. Four layers were designed as layers of outer, filler, electrical heating textile, and lining. The outer fabrics used two different densities of aramid woven fabrics (LD_ARW and HD_ARW), an aramid knit (AR_KT), and nonwoven (AR_NW). Fabricated graphene/polymer coated electrical heating textile (GR) exhibits a surface temperature of about 85 °C, a current of 0.12 A, and a power of 3 W when 30 V is applied. As composed with 4-layer, the surface temperature of LD_ARW and HD_ARW used as the outer for sample indicated less than 50 °C, due to their excellent heat resistance property; whereas, when AR_KT and AR_NW were used, the temperature was about 50 °C. This is because their fine fibers form high porosity that can entrap air. As a result of the thermal insulation properties, the temperature difference of each layer was in the order ΔT(GR-N3) (GR-Lining) (GR-Outer). In particular, when AR_NW was used as the outer fabric, ΔT(GR-Outer) was decreased by about 10 °C, compared with that of the other outer fabric. By the effect of relative humidity under dry 25% RH and comfortable 55% RH, the temperature difference was decreased under 55% RH; thus, the thermal insulation property was improved under comfortable humidity condition. Therefore, the best thermal insulation performance was exhibited when AR_NW was used as outer under 55% RH, and it is expected to expand its application to fabric heating element for protective clothing.

This study examined the effect of service employees&rsquo, resilience on deep acting in the job demands&ndash, resources model (JD-R model). It set and verified person&ndash, job fit and work engagement as double-mediation factors between service employees&rsquo, resilience and deep acting. To accomplish this, surveys targeting service employees working in the retail finance industry in Korea were administered. The analysis showed that resilience significantly increased person&ndash, job fit, and person&ndash, job fit improved work engagement. Additionally, it showed that work engagement improved deep acting. With regard to the double-mediation effect, the direct effect of resilience on deep acting was not statistically significant, but the double-mediation effect through person&ndash, job fit and work engagement was significant. In other words, person&ndash, job fit and work engagement fully mediated the relationship between resilience and deep acting. Additionally, person&ndash, job fit alone did not mediate the relationship between resilience and deep acting, but the independent mediation effect of work engagement was significant.

The main objective of this work was to prepare inulin (INL)/polyvinyl alcohol (PVA) biomaterials imprinted with arbutin (AR) as the target drug. INL from Jerusalem artichoke flour was extracted with hot water extraction method. INL/PVA biomaterials were synthesized with a casting method and a UV curing. The optimal UV curing time and sodium benzoate content were about 10 min and 0.1 wt%, respectively. The biomaterials were characterized by SEM and FT-IR analysis. Mechanical properties of prepared AR imprinted biomaterials were also investigated. AR release was examined with changes of pH at 36.5 °C. The AR release ratio was also investigated using artificial skin. It was found that AR was released constantly for 40 min. Results of drug release mechanism indicated that AR release followed the Fickian diffusion behavior, whereas drug release using artificial skin followed the non-Fickian diffusion behavior. Tyrosinase inhibitory (%) for AR imprinted biomaterials with/without the addition of GL were 58.8% and 79.2%, respectively.

In this study, we investigated the effects of solution characteristics on electrospinning behavior and nanoweb structure. We prepared a polyvinylidene fluoride (PVDF) solution by varying the ratios of N,N-dimethylformamide (DMF) and acetone in the solvent and fabricated nanowebs by electrospinning. We determined the solution characteristics of the PVDF solution with respect to the acetone ratio in the solvent. The effects of the solution characteristics on the electrospinning behavior were confirmed using a high-speed camera. We found significant differences in the electrospinning behavior. Thus, we investigated the effect of this difference on the morphology and structural properties of the fabricated nanoweb.

A poly(amic acid) (PAA) solution in xylene was prepared for electrospinning in order to fabricate fibers. However, jet breaking occurred at the point of the occurrence of whipping instability, resulting in forming micro-particles. This was an exceptional jet behavior compared with the general electro-spraying process that occurs directly from the surface of the polymer droplet. It is important to understand the mechanism of electrospinning and the instability of PAA in order to form fibers for mat deposition. Thus, the behavior of the jet breaking was clearly observed by a high-speed camera and the dynamic behavior of the jet was explored by an image analysis technique. Furthermore, polyacrylonitrile (PAN) was added to the PAA/xylene solution with various concentrations to change the elongation viscosity. Uniform diameter fibers were obtained by increasing the content of PAN to the level that the drag force between the polymer chains increased enough to overcome the drawing force. As a result the ...

Polymeric piezoelectric devices have been widely researched because of their many advantages including flexibility and easy preparation. Most previous studies investigated the conversion of wasted mechanical energy into usable electrical energy. In particular, high flexibility can be applied to a device that converts the acoustic energy discarded from the surrounding environment into usable energy. Such high flexibility can also be used in sound sensors in several fields. In this regard, for diverse application of polymer-based piezoelectric devices, investigation of the correlation between the vibration behavior caused by sound pressure and the energy conversion efficiency is essential. In this study, we successfully manufactured a flexible piezoelectric device with an integrated polymer and an electrode. Poly(vinylidene fluoride) (PVDF) was prepared via electrospinning and used as the active layer material of the piezoelectric device. To establish the electrodes of the composite piezoelectric device, a single-walled CNT dispersion was sprayed onto both sides of the prepared PVDF web. The electric properties and vibration behaviors of the piezoelectric devices were studied to reveal the effect of deformation on the piezoelectric performance, including the output voltage, impedance, displacement, and velocity of the vibrating device induced by sound waves. The output voltages of the devices tended to increase with better vibration characteristics due to sound pressure. In-depth analysis of the deformation behind the energy conversion in piezoelectricity could be important for the development of high-performance acoustic piezoelectric devices, such as wearable electronics, generators, and sensors.

Primary mediastinal leiomyoma is an extremely rare benign tumor of smooth muscle. Most common radiographic appearance is a well circumscribed heterogeneous solid mass. We reported a case of giant cyst-like lesion at the middle mediastinum, which was pathologically confirmed as a primary mediastinal leiomyoma.