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1.
Nat Commun ; 15(1): 3294, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632266

RESUMEN

Phase diagrams of materials are typically based on a static order parameter, but it faces challenges when distinguishing subtle phase changes, such as re-ordering. Here, we report a dynamic nonequilibrium order parameter termed re-order parameter to determine subtle phases and their transitions in interacting magnets. The dynamical precession of magnetization, so-called magnon, premises as a reliable re-order parameter of strong spin-orbit coupled magnets. We employ orthoferrites YFeO3 and its Mn-doped variations, where diverse magnetic phases, including canted antiferromagnetic (Γ4) and collinear antiferromagnetic (Γ1) states, have been well-established. Low-energy magnon uncovers the spin-orbit coupling-induced subtle magnetic structures, resulting in distinct terahertz emissions. The temporal and spectral parameters of magnon emission exhibit characteristics akin to BCS-type order parameters, constructing the magnetic phase diagram of Mn-doped YFeO3. This approach further reveals a concealed ferrimagnetic phase within the Γ1 state, underscoring its potential to search for hidden phases of materials, completing their phase diagrams.

2.
Biomed Mater ; 19(2)2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38324888

RESUMEN

In vitrohair follicle (HF) models are currently limited toex vivoHF organ cultures (HFOCs) or 2D models that are of low availability and do not reproduce the architecture or behavior of the hair, leading to poor screening systems. To resolve this issue, we developed a technology for the construction of a humanin vitrohair construct based on the assemblage of different types of cells present in the hair organ. First, we demonstrated that epithelial cells, when isolatedin vitro, have similar genetic signatures regardless of their dissection site, and their trichogenic potential is dependent on the culture conditions. Then, using cell aggregation techniques, 3D spheres of dermal papilla (DP) were constructed, and subsequently, epithelial cells were added, enabling the production and organization of keratins in hair, similar to what is seenin vivo. These reconstructed tissues resulted in the following hair compartments: K71 (inner root-sheath), K85 (matrix region), K75 (companion layer), and vimentin (DP). Furthermore, the new hair model was able to elongate similarly toex vivoHFOC, resulting in a shaft-like shape several hundred micrometers in length. As expected, when the model was exposed to hair growth enhancers, such as ginseng extract, or inhibitors, such as TGF-B-1, significant effects similar to thosein vivowere observed. Moreover, when transplanted into skin biopsies, the new constructs showed signs of integration and hair bud generation. Owing to its simplicity and scalability, this model fully enables high throughput screening of molecules, which allows understanding of the mechanism by which new actives treat hair loss, finding optimal concentrations, and determining the synergy and antagonism among different raw materials. Therefore, this model could be a starting point for applying regenerative medicine approaches to treat hair loss.


Asunto(s)
Dermis , Folículo Piloso , Humanos , Células Cultivadas , Organoides , Alopecia
3.
Nano Lett ; 24(8): 2529-2536, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38349889

RESUMEN

Our study highlights the versatility of tip-assisted terahertz spectroscopy in probing coherent magnons, the elementary quanta of spin waves in magnetic materials. We identify two distinct coherent magnon types in canted antiferromagnet YFeO3. The remarkable consistency with far-field terahertz spectroscopy in crucial magnon parameters, such as coherence time and resonance frequency, firmly establishes the credibility of tip-assisted terahertz spectroscopy. Notably, we capture more coherent ferromagnetic magnons near the sample surface, underscoring the strength of the technique. This approach paves the way for local, free-standing, and real-space investigations of spin waves in solid magnets.

5.
Ann Dermatol ; 35(Suppl 2): S275-S280, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38061721

RESUMEN

A 62-year-old man with multiple myeloma visited our clinic with multiple painful erythematous to purpuric nodules on his whole body. He received a skin biopsy which showed septal and lobular inflammation with vasculitis, and multiple amoebic organisms were found. Polymerase chain reaction and culture were performed and an Acanthamoeba triangularis infection was diagnosed. This is the first report on cutaneous acanthamoebiasis caused by A. triangularis, suggesting that A. triangularis should be regarded as a clinical pathogen that can cause ocular as well as disseminated infection.

10.
J Ginseng Res ; 47(3): 440-447, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37252273

RESUMEN

Background: The human hair follicle undergoes cyclic phases-anagen, catagen, and telogen-throughout its lifetime. This cyclic transition has been studied as a target for treating hair loss. Recently, correlation between the inhibition of autophagy and acceleration of the catagen phase in human hair follicles was investigated. However, the role of autophagy in human dermal papilla cells (hDPCs), which is involved in the development and growth of hair follicles, is not known. We hypothesized that acceleration of hair catagen phase upon inhibition of autophagy is due to the downregulation of Wnt/ß-catenin signaling in hDPCs, and that components of Panax ginseng extract can increase the autophagic flux in hDPCs. Methods: We generated an autophagy-inhibited condition using 3-methyladenine (3-MA), a specific autophagy inhibitor, and investigated the regulation of Wnt/ß-catenin signaling using the luciferase reporter assay, qRT-PCR, and western blot analysis. In addition, cells were cotreated with ginsenoside Re and 3-MA and their roles in inhibiting autophagosome formation were investigated. Results: We found that the unstimulated anagen phase dermal papilla region expressed the autophagy marker, LC3. Transcription of Wnt-related genes and nuclear translocation of ß-catenin were reduced after treatment of hDPCs with 3-MA. In addition, treatment with the combination of ginsenoside Re and 3-MA changed the Wnt activity and hair cycle by restoring autophagy. Conclusions: Our results suggest that autophagy inhibition in hDPCs accelerates the catagen phase by downregulating Wnt/ß-catenin signaling. Furthermore, ginsenoside Re, which increased autophagy in hDPCs, could be useful for reducing hair loss caused by abnormal inhibition of autophagy.

11.
Ann Dermatol ; 35(1): 23-31, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36750455

RESUMEN

BACKGROUND: The advent of fractionated picosecond (ps) lasers has provided an opportunity to explore new ways of creating microinjuries in the skin to induce skin rejuvenation. OBJECTIVE: To compare the efficacy and safety of diffractive optical element (DOE)-assisted ps neodymium: yttrium-aluminum-garnet (Nd:YAG) lasers with 532-nm and 1,064-nm wavelengths (532-nm and 1,064-nm Nd:YAG P-DOE) using a novel fractional handpiece for the treatment of photoaged skin. METHODS: An ex vivo guinea pig skin experiment was performed by evaluating the histology of the skin after 532-nm Nd:YAG P-DOE irradiation. A randomized, prospective, split-face study was performed on eight subjects with 532-nm and 1,064-nm Nd:YAG P-DOE. RESULTS: Based on the histological evaluation using ex vivo guinea pig skin, a reasonable safety profile and the potential to generate effective skin rejuvenation was observed using the 532-nm Nd:YAG P-DOE. Results demonstrated that both 532- and 1,064-nm Nd:YAG P-DOE were similarly effective in improving skin texture and skin pores; however, 532-nm Nd:YAG P-DOE was more effective in treating dyspigmentation. CONCLUSION: At a preliminary level, this study revealed that 532-nm and 1,064-nm ps Nd:YAG lasers using DOE fractional technology may improve photoaged skin. In conclusion, 532-nm Nd:YAG P-DOE may be especially beneficial for skin with epidermal pigmentary lesions.

12.
J Cosmet Dermatol ; 22(3): 831-836, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36345917

RESUMEN

BACKGROUND: Photobiomodulation therapy (PBMT) appears to be safe and effective for hair loss. Pulsed electromagnetic field therapy (PEMF) also has a positive biological effect on hair re-growth. OBJECTIVES: We evaluated the efficacy and safety of both PBMT and PEMF for the treatment of androgenetic alopecia (AGA). MATERIALS AND METHODS: This study was a 24-week, randomized, double-blind, sham device-controlled trial. We recruited 80 subjects with androgenetic alopecia. The subjects got treatment every week for the 1st 12 weeks, every other week for the next 8 weeks. PBMT entails 15-min therapy, and PEMF was carried out for 10 min. RESULTS: The baseline hair density was 114.57 (±28.75)/cm2 and 113.31 (±30.07)/cm2 in both treatment and control groups. After 24 weeks of treatment, the mean hair density increased to 139.37 (±31.4)/cm2 in the treatment group but only to 119.78 (±31.92)/cm2 in the control group. The difference between two groups was statistically significant (p < 0.05). Based on the global assessment of independent experts, the score was 0.41 (±0.62) in the treatment group and 0.07 (±0.45) in the control group. Only very mild erythema or irritation was reported, and no serious adverse reactions were reported. CONCLUSIONS: A combination of PBMT and PEMF is a valid and safe treatment option for AGA.


Asunto(s)
Terapia por Luz de Baja Intensidad , Humanos , Campos Electromagnéticos , Alopecia/terapia , Cabello , Eritema , Método Doble Ciego , Resultado del Tratamiento
14.
Sci Adv ; 8(47): eabq2479, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36427320

RESUMEN

Chiral fermions (CFs) in condensed matters, distinguished by right (+) or left (-) handedness, hold a promise for emergent quantum devices. Although a chiral anomaly induced current, Jchiral = J(+) - J(-), occurs in Weyl semimetals due to the charge imbalance of the CFs, monitoring spatial flow and temporal dynamics of Jchiral has not been demonstrated yet. Here, we report real-space imaging and control of Jchiral on the topological Dirac semimetal KZnBi at room temperature (RT) by near-field terahertz (THz) spectroscopy, establishing a relation for an electromagnetic control of Jchiral. In THz electric and external magnetic fields, we visualize a spatial flow of coherent Jchiral in macroscopic length scale and monitor its temporal dynamics in picosecond time scale, revealing its ultralong transport length around 100 micrometers. Such coherent Jchiral is further found to be controlled according to field directions, suggesting the feasibility of information science with topological Dirac semimetals at RT.

15.
J Cosmet Dermatol ; 21(11): 6174-6183, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35754308

RESUMEN

BACKGROUND: Many candidate genes for androgenetic alopecia (AGA) have been identified in studies of the Caucasians and some Asian populations. AIMS: This study aimed to confirm the known susceptibility genes reported in previous studies and find additional candidate genes for high-risk individuals for AGA in Korean population. PATIENTS/METHODS: We recapitulated the previously reported SNPs and identified the novel Korean AGA risk genetic variants using a Korean hospital-based AGA case and control samples. The population was consisting of 494 individuals (275 AGA cases and 146 controls). Using the 800 K SNPs of precision medical research array (PMRA SNP microarray chip) and imputation-based SNPs, 12 previous GWAS reports for AGA and a total of 62 160 SNPs were examined in our study samples. Also, we conducted the genome-wide association study (GWAS) by the logistic regression analyses for AGA cases and controls with controlling the age as the covariates. RESULTS: Among the 62 160 SNPs, a total of 1143 SNPs in 76 gene regions showed weak replication tendency with the p-values <0.05 and same direction of effects. Additionally, the GWAS results showed 110 SNPs in 13 independent regions with the suggestive p-values <1.00 × 10-5 . The most significantly replicated SNP resided on chromosome 20, which were similar to other AGA replication studies including Chinese study. The GWAS identified two SNPs (rs11010734 and rs2420640) increasing the risk for AGA in our study population. CONCLUSIONS: Our study would be a reference of the non-European studies to better understand AGA in different populations and ancestral contexts.


Asunto(s)
Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Polimorfismo de Nucleótido Simple , Pueblo Asiatico/genética , Alopecia/genética
16.
Adv Mater ; 34(33): e2200074, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35765199

RESUMEN

Layer-structured materials are of central importance in a wide range of research fields owing to their unique properties originating from their two dimensionality and anisotropy. Herein, quasi-2D layer-structured IMnV (I: alkali metals and V: pnictogen elements) compounds are investigated, which are potential antiferromagnetic (AFM) semiconductors. Single crystals of IMnV compounds are successfully grown using the self-flux method and their electronic and magnetic properties are analyzed in correlation with structural parameters. Combined with theoretical calculations, the structural analysis indicates that the variation in the bonding angle between VMnV is responsible for the change in the orbital hybridization of Mn and V, predominantly affecting their anisotropic semiconducting properties. Anisotropy in the magnetic properties is also found, where AFM ordering is expected to occur in the in-plane direction, as supported by spin-structure calculations. Furthermore, a possible ferromagnetic (FM) transition is discussed in relation to the vacancy defects. This study provides a candidate material group for AFM and FM spintronics and a basis for exploring magnetic semiconductors in quasi-2D layer-structured systems.

17.
Ann Dermatol ; 34(2): 105-109, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35450312

RESUMEN

Background: In South Korea, there have been few nationwide epidemiologic studies about premalignant actinic keratosis (AK), squamous cell carcinoma in situ (Bowen's disease), nonmelanoma skin cancer (NMSC), malignant melanoma of the skin (MM), Kaposi's sarcoma (KS), connective and soft tissue cancers, or mycosis fungoides (MF). Objective: Using a nationwide population-based study, we attempted to measure the incidence and the prevalence of the above-mentioned tumors in South Korea. Methods: The database we used included all claims in the Korean National Health Insurance program and the Korean Medical Aid program from 2008 to 2016. The International Classification of Diseases, 10th revision (ICD-10) was used to record diagnoses in this database. This data included AK, Bowen's disease, NMSC, MM, KS, connective and soft tissue cancers, and MF. Results: The age-standardized incidence and prevalence rate of AK, Bowen's disease, NMSC, MM, KS, connective and soft tissue cancers, as well as MF increased during the periods we investigated. The incidence and prevalence rate of AK and NMSC have increased two- to three-fold. In the case of Bowen's disease, MM, KS, connective and soft tissue cancers, or MF, we observed no significant tendency in age-standardized incidence or prevalence. Conclusion: We confirmed that the age-standardized incidence and prevalence rates of NMSC and AK tended to increase. These results might contribute to developing preventive and therapeutic strategies for skin cancers and may become a source for further studies.

19.
Biomed Rep ; 16(3): 16, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35223000

RESUMEN

Androgenic alopecia is a hair loss disease mediated by dihydrotestosterone (DHT) and is currently treated using minoxidil, finasteride, or low-level laser therapy. However, these treatments have side-effects, indicating the need for an alternative treatment. In the present study, it was demonstrated that inaudible sound at 30 kHz significantly induced proliferative and anti-apoptotic effects in human dermal papilla cells (hDPCs) and outer root sheath keratinocytes. Cell viability assay, ELISA, reverse transcription quantitative PCR and TUNEL assays were performed to evaluate the effect of inaudible sound. Inaudible sound was also demonstrated to significantly inhibit the hair loss signals induced by DHT treatment in hDPCs. Furthermore, inaudible sound significantly induced hair follicle (HF) elongation and hair matrix keratinocyte proliferation in human HF organ culture. Overall, the results suggested that inaudible sound may be effective in treating hair loss and could be used to develop a new hair loss treatment approach.

20.
ACS Nano ; 16(2): 2024-2031, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35124964

RESUMEN

Metavalent bonding is crucial for the determination of phase transition and improvement of device performance in phase-change materials, which are attracting interest for use in memory devices. Although monitoring dielectric and phononic parameters provides a direct measure of the metavalent bonding, the control of phase-change phenomena and metavalent bonding in the dynamical regime has yet to be demonstrated. This study reports the photoenhanced metavalent bonding and resulting hidden metallic crystalline state of Ti-doped Sb2Te3, a representative phase-change material with ultralong sustainability. Using ultrafast terahertz spectroscopy, Ti0.4Sb2Te3 was discovered to possess ultralong pump-probe dynamics, which is retained over hundreds of picoseconds, unlike the short-lived state of undoped Sb2Te3. Moreover, for Ti0.4Sb2Te3 during the long-lived transmission change, the infrared-active phonon is highly softened, even more than the amount of a thermal phonon shift, indicating the photoenhancement of lattice anharmonicity. Such a long-lived relaxation implies photoinduced transition into a crystalline state of ultrastrong metavalent bonding in Ti0.4Sb2Te3, on the basis of comparisons of the dynamical dielectric constant and temporal phonon shift. Our results show the realization of photoengineering of phase-change materials by tuning electron sharing or transferring.

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