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1.
Mol Cancer ; 22(1): 200, 2023 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-38066564

RESUMEN

BACKGROUND: Commercial anti-CD19 chimeric antigen receptor T-cell therapies (CART19) are efficacious against advanced B-cell non-Hodgkin lymphoma (NHL); however, most patients ultimately relapse. Several mechanisms contribute to this failure, including CD19-negative escape and CAR T dysfunction. All four commercial CART19 products utilize the FMC63 single-chain variable fragment (scFv) specific to a CD19 membrane-distal epitope and characterized by slow association (on) and dissociation (off) rates. We hypothesized that a novel anti-CD19 scFv that engages an alternative CD19 membrane-proximal epitope independent of FMC63 and that is characterized by faster on- and off-rates could mitigate CART19 failure and improve clinical efficacy. METHODS: We developed an autologous CART19 product with 4-1BB co-stimulation using a novel humanized chicken antibody (h1218). This antibody is specific to a membrane-proximal CD19 epitope and harbors faster on/off rates compared to FMC63. We tested h1218-CART19 in vitro and in vivo using FMC63-CART19-resistant models. We conducted a first-in-human multi-center phase I clinical trial to test AT101 (clinical-grade h1218-CART19) in patients with relapsed or refractory (r/r) NHL. RESULTS: Preclinically, h1218- but not FMC63-CART19 were able to effectively eradicate lymphomas expressing CD19 point mutations (L174V and R163L) or co-expressing FMC63-CAR19 as found in patients relapsing after FMC63-CART19. Furthermore, h1218-CART19 exhibited enhanced killing of B-cell malignancies in vitro and in vivo compared with FMC63-CART19. Mechanistically, we found that h1218-CART19 had reduced activation-induced cell death (AICD) and enhanced expansion compared to FMC63-CART19 owing to faster on- and off-rates. Based on these preclinical results, we performed a phase I dose-escalation trial, testing three dose levels (DL) of AT101 (the GMP version of h1218) using a 3 + 3 design. In 12 treated patients (7 DLBCL, 3 FL, 1 MCL, and 1 MZL), AT101 showed a promising safety profile with 8.3% grade 3 CRS (n = 1) and 8.3% grade 4 ICANS (n = 1). In the whole cohort, the overall response rate was 91.7%, with a complete response rate of 75.0%, which improved to 100% in DL-2 and -3. AT101 expansion correlates with CR and B-cell aplasia. CONCLUSIONS: We developed a novel, safe, and potent CART19 product that recognizes a membrane-proximal domain of CD19 with fast on- and off-rates and showed significant efficacy and promising safety in patients with relapsed B-cell NHL. TRIAL REGISTRATION: NCT05338931; Date: 2022-04-01.


Asunto(s)
Linfoma no Hodgkin , Receptores de Antígenos de Linfocitos T , Receptores Quiméricos de Antígenos , Humanos , Anticuerpos , Antígenos CD19 , Epítopos/metabolismo , Inmunoterapia Adoptiva/efectos adversos , Linfoma no Hodgkin/terapia , Linfoma no Hodgkin/metabolismo , Recurrencia Local de Neoplasia/metabolismo , Receptores Quiméricos de Antígenos/metabolismo , Receptores de Antígenos de Linfocitos T/antagonistas & inhibidores
2.
J Environ Manage ; 345: 118833, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37639910

RESUMEN

In the present study, through the laboratory-to-field scale experiments and trials, we report the development and evaluation of an integrated oil-spill response system capable of oil collection, recovery (separation), and storage, for a timely and effective response to the initial stage of oil-spill accidents. With the laboratory-scale experiments, first, we evaluate that the water-surface waves tend to abate the oil recovery rate below 80% (it is above 95% for the optimized configuration without the waves), which is overcome by installing the hydrophilic (and oleophobic) porous structures at the inlet and/or near the water outlet of the separator. In the follow-up meso-scale towing tank tests with a scaled-up prototype, (i) we optimize the maneuverability of the assembled system depending on the speed and existence of waves, and (ii) evaluate the oil recovery performance (more than 80% recovery for the olive oil and Bunker A fuel oil). Although more thorough investigations and improvements are needed, a recovery rate of over 50% can be achieved for the newly enforced marine fuel oil (low sulfur fuel oil, LSFO) that was not targeted at the time of development. Finally, we perform a series of field tests with a full-scale system, to evaluate the rapid deployment and operational stability in the real marine environment. The overall floating balance and coordination of each functional part are sustained to be stable during the straight and rotary maneuvers up to the speed of 5 knots. Also, the collection of the floating debris (mimicking the spilled oil) is demonstrated in the field test. The present system is now being tested by the Korea Coast Guard and we believe that it will be very powerful to prevent the environmental damage due to the oil spills.


Asunto(s)
Aceites Combustibles , Contaminación por Petróleo , Bahías , Laboratorios , Agua
3.
Curr Issues Mol Biol ; 44(10): 5086-5103, 2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36286060

RESUMEN

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract and is characterized by recurrent chronic inflammation and mucosal damage of the gastrointestinal tract. Recent studies have demonstrated that bamboo shoot (BS) and Artemisia capillaris (AC) extracts enhance anti-inflammatory effects in various disease models. However, it is uncertain whether there is a synergistic protective effect of BS and AC in dextran sodium sulfate (DSS)-induced colitis. In the current study, we tested the combined effects of BS and AC extracts (BA) on colitis using in vivo and in vitro models. Compared with control mice, oral administration of DSS exacerbated colon length and increased the disease activity index (DAI) and histological damage. In DSS-induced colitis, treatment with BA significantly alleviated DSS-induced symptoms such as colon shortening, DAI, histological damage, and colonic pro-inflammatory marker expression compared to single extracts (BS or AC) treatment. Furthermore, we found BA treatment attenuated the ROS generation, F-actin formation, and RhoA activity compared with the single extract (BS or AC) treatment in DSS-treated cell lines. Collectively, these findings suggest that BA treatment has a positive synergistic protective effect on colonic inflammation compared with single extracts, it may be a highly effective complementary natural extract mixture for the prevention or treatment of IBD.

4.
Biochem Biophys Res Commun ; 534: 639-645, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33220923

RESUMEN

The intestinal epithelium is one of the fastest renewing tissues in mammals and is a barrier against toxic substances such as alcohol. Excessive alcohol can induce intestinal damage leading to intestinal bowel diseases. Thus, the control of small intestinal epithelial cell (IEC) regeneration is thought to be important for homeostasis in response to epithelium damage. However, reports on how epithelial cells respond to small intestinal damage are scarce. We investigated the effects of alcohol consumption on small intestinal epithelial cells of mice. To verify that alcohol altered the small intestinal epithelium, we used 8-10 weeks old male C57BL/6J mice for models of chronic and binge alcohol consumption (the NIAAA model) in addition to an organoid model. Alcohol promoted the proliferative activity of IECs and intestinal stem cells (ISCs) in intestinal crypts. Alcohol consumption increased expression of the proliferation marker cyclin D1 and activated the p44/42 MAPK (Erk1/2) signaling pathway in small intestinal epithelial cells. The Wnt target genes were markedly increased in IECs from alcohol-treated mice. In the small intestinal organoid model exposed to alcohol, the organoid area and numbers of buds increased with alcohol concentrations up to 0.5% similar to in vivo observations. These results suggest that alcohol consumption stimulates the proliferation of small intestinal epithelial cells via Wnt signaling.


Asunto(s)
Etanol/toxicidad , Mucosa Intestinal/efectos de los fármacos , Alcoholismo/metabolismo , Alcoholismo/patología , Animales , Consumo Excesivo de Bebidas Alcohólicas/metabolismo , Consumo Excesivo de Bebidas Alcohólicas/patología , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Intestino Delgado/efectos de los fármacos , Intestino Delgado/metabolismo , Intestino Delgado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Organoides/efectos de los fármacos , Organoides/metabolismo , Organoides/patología , Células Madre/efectos de los fármacos , Células Madre/metabolismo , Células Madre/patología , Vía de Señalización Wnt/efectos de los fármacos , Vía de Señalización Wnt/genética
5.
J Am Chem Soc ; 142(50): 21059-21067, 2020 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-33217232

RESUMEN

Recently, halide perovskites have gained significant attention from the perspective of efficient spintronics owing to the Rashba effect. This effect occurs as a consequence of strong spin-orbit coupling under a noncentrosymmetric environment, which can be dynamic and/or static. However, there exist intense debates on the origin of broken inversion symmetry since the halide perovskites typically crystallize into a centrosymmetric structure. In order to clarify the issue, we examine both dynamic and static effects in the all-inorganic CsPbBr3 and organic-inorganic CH3NH3PbBr3 (MAPbBr3) perovskite single crystals by employing temperature- and polarization-dependent photoluminescence excitation spectroscopy. The perovskite single crystals manifest the dynamic effect by photon recycling in the indirect Rashba gap, causing dual peaks in the photoluminescence. However, the effect vanishes in CsPbBr3 at low temperatures (<50 K) accompanied by a striking color change of the crystal, arising presumably from lower degrees of freedom for inversion symmetry breaking associated with the thermal motion of the spherical Cs cation compared with the polar MA cation in MAPbBr3. We also show that the static Rashba effect occurs only in MAPbBr3 below 90 K, presumably due to surface reconstruction via MA-cation ordering, which likely extends across a few layers from the crystal surface to the interior. We further demonstrate that this static Rashba effect can be completely suppressed upon surface treatment with polymethyl methacrylate (PMMA) coating. We believe that our results provide a rationale for the Rashba effects in halide perovskites.

6.
Nano Lett ; 18(7): 4523-4530, 2018 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-29921125

RESUMEN

Chemical treatment using bis(trifluoromethane) sulfonimide (TFSI) was shown to be particularly effective for increasing the photoluminescence (PL) of monolayer (1L) MoS2, suggesting a convenient method for overcoming the intrinsically low quantum yield of this material. However, the underlying atomic mechanism of the PL enhancement has remained elusive. Here, we report the microscopic origin of the defect healing observed in TFSI-treated 1L-MoS2 through a correlative combination of optical characterization and atomic-scale scanning transmission electron microscopy, which showed that most of the sulfur vacancies were directly repaired by the extrinsic sulfur atoms produced from the dissociation of TFSI, concurrently resulting in a significant PL enhancement. Density functional theory calculations confirmed that the reactive sulfur dioxide molecules that dissociated from TFSI can be reduced to sulfur and oxygen gas at the vacancy site to form strongly bound S-Mo. Our results reveal how defect-mediated nonradiative recombination can be effectively eliminated by a simple chemical treatment method, thereby advancing the practical applications of monolayer semiconductors.

7.
Int J Mol Sci ; 20(23)2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31757050

RESUMEN

In our ongoing research to discover natural products with neuroprotective effects, hyperoside (quercetin 3-O-galactoside) was isolated from Acer tegmentosum, which has been used in Korean traditional medicine to treat liver-related disorders. Here, we demonstrated that hyperoside protects cultured dopaminergic neurons from death via reactive oxygen species (ROS)-dependent mechanisms, although other relevant mechanisms of hyperoside activity remain largely uncharacterized. For the first time, we investigated the neuroprotective effects of hyperoside on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in neurons, and the possible underlying mechanisms. Hyperoside significantly ameliorated the loss of neuronal cell viability, lactate dehydrogenase release, excessive ROS accumulation and mitochondrial membrane potential dysfunction associated with 6-OHDA-induced neurotoxicity. Furthermore, hyperoside treatment activated the nuclear erythroid 2-related factor 2 (Nrf2), an upstream molecule of heme oxygenase-1 (HO-1). Hyperoside also induced the expression of HO-1, an antioxidant response gene. Remarkably, we found that the neuroprotective effects of hyperoside were weakened by an Nrf2 small interfering RNA, which blocked the ability of hyperoside to inhibit neuronal death, indicating the vital role of HO-1. Overall, we show that hyperoside, via the induction of Nrf2-dependent HO-1 activation, suppresses neuronal death caused by 6-OHDA-induced oxidative stress. Moreover, Nrf2-dependent HO-1 signaling activation represents a potential preventive and therapeutic target in Parkinson's disease management.


Asunto(s)
Antioxidantes/farmacología , Neuronas Dopaminérgicas/efectos de los fármacos , Hemo-Oxigenasa 1/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Fármacos Neuroprotectores/farmacología , Quercetina/análogos & derivados , Acer/química , Línea Celular Tumoral , Neuronas Dopaminérgicas/metabolismo , Humanos , Estrés Oxidativo , Oxidopamina/toxicidad , Quercetina/farmacología , Transducción de Señal
8.
Exp Dermatol ; 27(3): 285-288, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29392819

RESUMEN

Skin cancer is the most common type of cancer. The incidence rate of skin cancer has continuously increased over the past decades. In an effort to discover novel anticancer agents, we identified a novel tubulin inhibitor STK899704, which is structurally distinct from other microtubule-binding agents such as colchicine, vinca alkaloids and taxanes. STK899704 inhibited microtubule polymerization leading to mitotic arrest and suppressed the proliferation of various cancer cell lines as well as multidrug resistance cancer cell lines. In this study, our investigation is further extended into animal model to evaluate the effect of STK899704 on skin carcinogenesis in vivo. Surprisingly, almost 80% of the tumors treated with STK899704 were regressed with a one-fifth reduction in tumor volume. Furthermore, the efficacy of STK899704 was nearly 2 times higher than that of 5-fluorouracil, a widely used skin cancer therapeutic. Overall, our results suggest that STK899704 is a promising anticancer chemotherapeutic that may replace existing therapies, particularly for skin cancer.


Asunto(s)
Benzofuranos/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Moduladores de Tubulina/uso terapéutico , 9,10-Dimetil-1,2-benzantraceno , Animales , Antimetabolitos Antineoplásicos/uso terapéutico , Carcinogénesis , Colchicina/uso terapéutico , Modelos Animales de Enfermedad , Fluorouracilo/uso terapéutico , Masculino , Ratones , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/patología , Acetato de Tetradecanoilforbol , Tubulina (Proteína)/metabolismo
9.
Arthroscopy ; 34(10): 2810-2818, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30173911

RESUMEN

PURPOSE: To compare union rates and clinical and radiologic outcomes after arthroscopic and open bone grafting and internal fixation for unstable scaphoid nonunions. METHODS: Between March 2009 and November 2014, patients with unstable scaphoid nonunion underwent arthroscopic (group A) or open (group O) bone grafting and internal fixation. One senior surgeon alternatively performed either arthroscopic or open osteosynthesis for the same surgical indications. Visual analog scale score, grip strength, active range of motion, Mayo wrist score (MWS), and Disabilities of Arm, Shoulder, and Hand score were assessed preoperatively and postoperatively. Union was determined by computed tomography 8 to 10 weeks postoperatively with bridging trabecula at the nonunion site. Scapholunate angle (SLA), radiolunate angle (RLA), and lateral intrascaphoid angle (LISA), plus height/length ratio (HLR) served to gauge carpal bone alignment in preoperative and postoperative radiographs. Those outcomes of patients with carpal collapse deformities, who met following conditions; (1) LISA of >45° or HLR of >0.65 on computed tomography images or (2) SLA of >60° or RLA of >10° on plain radiographs, were also compared. RESULTS: Overall, 62 patients qualified for study (group A, 28; group O, 34). Union rates did not differ by patient subset (group A, 96.4%; group O, 97.1%; P â‰’ 1); and visual analog scale score, grip strength, range of motion, Mayo Wrist Score, and Disabilities of Arm, Shoulder, and Hand scores were similar at last follow-up. In radiographic assessments, SLA, RLA, and LISA were similar, whereas scaphoid HLR excelled through open technique (group A, 0.59 ± 0.07; group O, 0.55 ± 0.05; P = .002). Subgroup analysis of patients with carpal collapse deformities (group A, 9; group O, 14) showed that all radiographic measures in group A (vs group O) reflected lesser correction (SLA, 56.7° ± 7.3° vs 49.2°±9.1° [P = .049]; RLA, 9.2° ± 2.0° vs 5.7° ± 3.0° [P = .005]; LISA, 34.8° ± 4.8° vs 25.6° ± 13.0° [P = .028]; HLR, 0.66 ± 0.04 vs 0.54 ± 0.07 [P < .001]). CONCLUSIONS: Arthroscopic and open bone grafting and internal fixation in treating unstable scaphoid nonunions, did not show any significant differences in clinical and radiologic outcomes at the minimum of 2 years after operation. In scaphoid nonunions with carpal collapse deformities, open bone grafting restored better carpal alignment than arthroscopic bone grafting, although there were no differences in clinical outcomes between the 2 techniques. LEVEL OF EVIDENCE: Level III, retrospective comparative study.


Asunto(s)
Artroscopía/métodos , Trasplante Óseo/métodos , Fijación Interna de Fracturas/métodos , Fracturas no Consolidadas/cirugía , Hueso Escafoides/lesiones , Hueso Escafoides/cirugía , Adulto , Femenino , Fracturas no Consolidadas/diagnóstico por imagen , Fracturas no Consolidadas/fisiopatología , Fuerza de la Mano/fisiología , Humanos , Masculino , Persona de Mediana Edad , Dolor Postoperatorio , Rango del Movimiento Articular/fisiología , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Articulación de la Muñeca/cirugía , Adulto Joven
10.
Front Microbiol ; 15: 1355599, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38706966

RESUMEN

The emergence of anti-influenza drug-resistant strains poses a challenge for influenza therapy due to mutations in the virus's surface protein. Recently, there has been increasing interest in combination therapy consisting of two or more drugs as a potential alternative approach, aiming to enhance therapeutic efficacy. In this study, we investigated a novel synergistic therapy with a vertical effect using a single-domain VL-HA1-specific antibody against H1N1/PR8 and a horizontal effect using an RNA catalytic antibody with broad-spectrum influenza antiviral drug. We isolated a single-domain VL-HA1-specific (NVLH8) antibody binding to the virus particles showing a neutralizing activity against influenza virus A, specifically H1N1/PR8, as determined by the reduction in plaque number and lower viral HA protein expression in vitro. The neutralizing antibody likely prevented the viral entry, specifically at the viral genome-releasing step. Additionally, the 3D8 scFv hydrolyzed viral RNAs in the cytoplasm, including mRNA, vRNA, and cRNA in MDCK cells. The combined treatment of neutralizing antibodies for a vertical effect and 3D8 scFv for a horizontal effect produced a synergistic effect providing a novel approach against viral diseases when compared with a single treatment. Our results indicated that combining treatment, in particular two proteins exhibiting different mechanisms of action increased the antiviral activity against the influenza virus.

11.
J Bone Joint Surg Am ; 106(9): 817-822, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38381844

RESUMEN

BACKGROUND: In the setting of periprosthetic humeral fractures, the humeral stem of the implant represents a substantial challenge to the optimal method of proximal fixation. This study aimed to compare the initial biomechanical stability provided by cerclage cables with a locking plate insert versus bicortical locking screws (i.e., the gold standard for fixation) in fresh cadaveric humeri. METHODS: After calculating the sample size, we utilized 10 sets of cadaveric specimens and created a 5-mm osteotomy gap 120 mm distal to the tip of the greater tuberosity, simulating a Wright and Cofield type-B periprosthetic humeral fracture on each specimen. Using 3 locking screws for distal fragment fixation, identical in all specimens, the specimens were assigned to Group A (3 cerclage cables with a plate insert) or Group B (3 locking bicortical screws) for proximal fragment fixation. Biomechanical tests included stiffness in varus and valgus bending, torsion, and axial compression, and a single load to failure. RESULTS: No significant differences were observed in the biomechanical metrics between the 2 groups. CONCLUSIONS: Our study revealed that fixation with use of cerclage cables with a plate insert demonstrated biomechanical stability comparable with that of bicortical locking screw fixation when addressing the proximal fragment in Wright and Cofield type-B periprosthetic humeral fractures. CLINICAL RELEVANCE: For proximal fragment fixation of periprosthetic humeral fractures, cerclage cables with a plate insert can be utilized as an effective fixation method that offers initial fixation strength that is comparable to the use of 3 locking bicortical screws.


Asunto(s)
Placas Óseas , Tornillos Óseos , Cadáver , Fijación Interna de Fracturas , Fracturas Periprotésicas , Humanos , Fracturas Periprotésicas/cirugía , Fracturas Periprotésicas/etiología , Fijación Interna de Fracturas/instrumentación , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/efectos adversos , Fenómenos Biomecánicos , Anciano , Femenino , Masculino , Fracturas del Húmero/cirugía , Anciano de 80 o más Años
12.
Sci Rep ; 14(1): 8472, 2024 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-38605110

RESUMEN

With the lifting of COVID-19 non-pharmaceutical interventions, the resurgence of common viral respiratory infections was recorded in several countries worldwide. It facilitates viral co-infection, further burdens the already over-stretched healthcare systems. Racing to find co-infection-associated efficacy therapeutic agents need to be rapidly established. However, it has encountered numerous challenges that necessitate careful investigation. Here, we introduce a potential recombinant minibody-associated treatment, 3D8 single chain variable fragment (scFv), which has been developed as a broad-spectrum antiviral drug that acts via its nucleic acid catalytic and cell penetration abilities. In this research, we demonstrated that 3D8 scFv exerted antiviral activity simultaneously against both influenza A viruses (IAVs) and coronaviruses in three established co-infection models comprising two types of coronaviruses [beta coronavirus-human coronavirus OC43 (hCoV-OC43) and alpha coronavirus-porcine epidemic diarrhea virus (PEDV)] in Vero E6 cells, two IAVs [A/Puerto Rico/8/1934 H1N1 (H1N1/PR8) and A/X-31 (H3N2/X-31)] in MDCK cells, and a combination of coronavirus and IAV (hCoV-OC43 and adapted-H1N1) in Vero E6 cells by a statistically significant reduction in viral gene expression, proteins level, and approximately around 85%, 65%, and 80% of the progeny of 'hCoV-OC43-PEDV', 'H1N1/PR8-H3N2/X-31', and 'hCoV-OC43-adapted-H1N1', respectively, were decimated in the presence of 3D8 scFv. Taken together, we propose that 3D8 scFv is a promising broad-spectrum drug for treatment against RNA viruses in co-infection.


Asunto(s)
Coinfección , Coronavirus Humano OC43 , Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Anticuerpos de Cadena Única , Humanos , ARN/metabolismo , Subtipo H3N2 del Virus de la Influenza A , Anticuerpos de Cadena Única/farmacología , Anticuerpos de Cadena Única/metabolismo
13.
ACS Nano ; 18(1): 220-228, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38127273

RESUMEN

The efficiency of light emission is a critical performance factor for monolayer transition metal dichalcogenides (1L-TMDs) for photonic applications. While various methods have been studied to compensate for lattice defects to improve the quantum yield (QY) of 1L-TMDs, exciton-exciton annihilation (EEA) is still a major nonradiative decay channel for excitons at high exciton densities. Here, we demonstrate that the combined use of a proximal Au plate and a negative electric gate bias (NEGB) for 1L-WS2 provides a dramatic enhancement of the exciton lifetime at high exciton densities with the corresponding QY enhanced by 30 times and the EEA rate constant decreased by 80 times. The suppression of EEA by NEGB is attributed to the reduction of the defect-assisted EEA process, which we also explain with our theoretical model. Our results provide a synergetic solution to cope with EEA to realize high-intensity 2D light emitters using TMDs.

14.
J Immunol ; 187(6): 3338-46, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21832158

RESUMEN

Organ-specific autoimmune diseases are usually characterized by repeated cycles of remission and recurrent inflammation. However, where the autoreactive memory T cells reside in between episodes of recurrent inflammation is largely unknown. In this study, we have established a mouse model of chronic uveitis characterized by progressive photoreceptor cell loss, retinal degeneration, focal retinitis, retinal vasculitis, multifocal choroiditis, and choroidal neovascularization, providing for the first time to our knowledge a useful model for studying long-term pathological consequences of chronic inflammation of the neuroretina. We show that several months after inception of acute uveitis, autoreactive memory T cells specific to retinal autoantigen, interphotoreceptor retinoid-binding protein (IRBP), relocated to bone marrow (BM). The IRBP-specific memory T cells (IL-7Rα(High)Ly6C(High)CD4(+)) resided in BM in resting state but upon restimulation converted to IL-17/IFN-γ-expressing effectors (IL-7Rα(Low)Ly6C(Low)CD4(+)) that mediated uveitis. We further show that T cells from STAT3-deficient (CD4-STAT3KO) mice are defective in α4ß1 and osteopontin expression, defects that correlated with inability of IRBP-specific memory CD4-STAT3KO T cells to traffic into BM. We adoptively transferred uveitis to naive mice using BM cells from wild-type mice with chronic uveitis but not BM cells from CD4-STAT3KO, providing direct evidence that memory T cells that mediate uveitis reside in BM and that STAT3-dependent mechanism may be required for migration into and retention of memory T cells in BM. Identifying BM as a survival niche for T cells that cause uveitis suggests that BM stromal cells that provide survival signals to autoreactive memory T cells and STAT3-dependent mechanisms that mediate their relocation into BM are attractive therapeutic targets that can be exploited to selectively deplete memory T cells that drive chronic inflammation.


Asunto(s)
Células de la Médula Ósea/inmunología , Linfocitos T CD4-Positivos/inmunología , Memoria Inmunológica/inmunología , Factor de Transcripción STAT3/inmunología , Uveítis/inmunología , Traslado Adoptivo , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/patología , Autoinmunidad/inmunología , Quimiotaxis de Leucocito/inmunología , Enfermedad Crónica , Modelos Animales de Enfermedad , Electrorretinografía , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Transcripción STAT3/metabolismo , Tomografía de Coherencia Óptica , Uveítis/patología
15.
Nature ; 447(7145): 714-9, 2007 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-17554307

RESUMEN

Teleosts comprise more than half of all vertebrate species and have adapted to a variety of marine and freshwater habitats. Their genome evolution and diversification are important subjects for the understanding of vertebrate evolution. Although draft genome sequences of two pufferfishes have been published, analysis of more fish genomes is desirable. Here we report a high-quality draft genome sequence of a small egg-laying freshwater teleost, medaka (Oryzias latipes). Medaka is native to East Asia and an excellent model system for a wide range of biology, including ecotoxicology, carcinogenesis, sex determination and developmental genetics. In the assembled medaka genome (700 megabases), which is less than half of the zebrafish genome, we predicted 20,141 genes, including approximately 2,900 new genes, using 5'-end serial analysis of gene expression tag information. We found single nucleotide polymorphisms (SNPs) at an average rate of 3.42% between the two inbred strains derived from two regional populations; this is the highest SNP rate seen in any vertebrate species. Analyses based on the dense SNP information show a strict genetic separation of 4 million years (Myr) between the two populations, and suggest that differential selective pressures acted on specific gene categories. Four-way comparisons with the human, pufferfish (Tetraodon), zebrafish and medaka genomes revealed that eight major interchromosomal rearrangements took place in a remarkably short period of approximately 50 Myr after the whole-genome duplication event in the teleost ancestor and afterwards, intriguingly, the medaka genome preserved its ancestral karyotype for more than 300 Myr.


Asunto(s)
Evolución Molecular , Genoma/genética , Oryzias/genética , Animales , China , Cromosomas/genética , Proteínas de Peces/genética , Genómica , Humanos , Japón , Oryzias/clasificación , Filogenia , Polimorfismo de Nucleótido Simple/genética , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Taiwán , Factores de Tiempo
16.
Mediators Inflamm ; 2013: 359674, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24204098

RESUMEN

STAT3 regulates CD4+ T cell survival and differentiation. However, its effects on CD8+ T cells are not well understood. Here, we show that in comparison to WT CD8+ T cells, STAT3-deficient CD8+ T cells exhibit a preactivated memory-like phenotype, produce more IL-2, proliferate faster, and are more sensitive to activation-induced cell death (AICD). The enhanced proliferation and sensitivity to AICD correlated with downregulation of class-O forkhead transcription factors (FoxO1, FoxO3A), p21(waf1), p27(KIP1), Bcl-2, OX-40, and upregulation of FasL, Bax, and Bad. We examined whether STAT3-deficient CD8+ T cells can mount effective response during herpes simplex virus (HSV-1) infection and experimental autoimmune uveitis (EAU). Compared to WT mice, HSV-1-infected STAT3-deficient mice (STAT3KO) produced less IFN-γ and virus-specific KLRG-1+ CD8+ T cells. STAT3KO mice are also resistant to EAU and produced less IL-17-producing Tc17 cells. Resistance of STAT3KO to EAU correlated with marked expansion of IL-10-producing regulatory CD8+ T cells (CD8-Treg) implicated in recovery from autoimmune encephalomyelitis. Thus, increases of IL-6-induced STAT3 activation observed during inflammation may inhibit expansion of CD8-Tregs, thereby impeding recovery from uveitis. These results suggest that STAT3 is a potential therapeutic target for upregulating CD8+ T cell-mediated responses to viruses and suggest the successful therapeutic targeting of STAT3 as treatment for uveitis, derived, in part, from promoting CD8-Treg expansion.


Asunto(s)
Linfocitos T CD8-positivos/citología , Herpes Simple/metabolismo , Interleucina-10/metabolismo , Factor de Transcripción STAT3/genética , Uveítis/inmunología , Animales , Apoptosis , Enfermedades Autoinmunes/inmunología , Proliferación Celular , Separación Celular , Citometría de Flujo , Regulación de la Expresión Génica , Herpes Simple/virología , Herpesvirus Humano 1 , Inflamación , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fenotipo , Factor de Transcripción STAT3/metabolismo , Regulación hacia Arriba , Uveítis/virología
17.
Materials (Basel) ; 16(21)2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37959503

RESUMEN

Precast concrete (PC) structures have many advantages, but their use in the construction of middle- to high-rise buildings is limited. The construction of PC structures requires skills in various operations such as transportation, assembly, lifting, and structural soundness. In particular, regarding the seismic design of PC structures, it is necessary to clearly evaluate whether they have the same structural performance and usability as integral RC (cast-in-place) structures. In this paper, an experimental study was conducted to investigate whether PC members can achieve a seismic performance equivalent to that of RC members in beam-column joints, which are representative moment-resisting frames. The main variables are the two types of structural systems (intermediate and special moment-resisting frames) and the design flexural strength ratio of the columns and beams. The experimental and analytical results showed that the seismic performance of the PC specimens was equivalent to that of the RC specimens in terms of strength, stiffness, energy dissipation, and strain distribution, except for the specimen with splice sleeve bond failure of the column reinforcement (poor filling of the internal mortar). In addition, the I series satisfied the present emulation evaluation criteria for special moment-resisting frames of PC structures, confirming the possibility of applying intermediate moment-resisting frames.

18.
Brain Tumor Res Treat ; 10(4): 265-269, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36347641

RESUMEN

Meningiomas are the most common benign brain tumors, and most of them originate from the dura mater. However, in some cases, they can originate from the choroid plexus, and they are rarely found in the posterior cranial fossa. A 63-year-old female patient presented with dizziness and swallowing difficulty and was found to have a homogeneously enhancing mass in the right posterior cranial fossa. Mass removal was performed through retrosigmoid suboccipital craniotomy, and the mass was confirmed to originate from the choroid plexus. The pathological diagnosis was meningothelial meningioma. The patient had temporary swallowing difficulty but recovered without any neurological sequelae. We report a rare case of a lower cerebellopontine angle meningioma without dural attachment originating from the choroid plexus of the foramen of Luschka.

19.
Microorganisms ; 10(8)2022 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-36013970

RESUMEN

Outbreaks of viral diseases, which cause morbidity and mortality in animals and humans, are increasing annually worldwide. Vaccines, antiviral drugs, and antibody therapeutics are the most effective tools for combating viral infection. The ongoing coronavirus disease 2019 pandemic, in particular, raises an urgent need for the development of rapid and broad-spectrum therapeutics. Current antiviral drugs and antiviral antibodies, which are mostly specific at protein levels, have encountered difficulties because the rapid evolution of mutant viral strains resulted in drug resistance. Therefore, degrading viral genomes is considered a novel approach for developing antiviral drugs. The current article highlights all potent candidates that exhibit antiviral activity by digesting viral genomes such as RNases, RNA interference, interferon-stimulated genes 20, and CRISPR/Cas systems. Besides that, we introduce a potential single-chain variable fragment (scFv) that presents antiviral activity against various DNA and RNA viruses due to its unique nucleic acid hydrolyzing characteristic, promoting it as a promising candidate for broad-spectrum antiviral therapeutics.

20.
Viruses ; 14(5)2022 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-35632846

RESUMEN

Emerging Oseltamivir-resistant influenza strains pose a critical public health threat due to antigenic shifts and drifts. We report an innovative strategy for controlling influenza A infections by use of a novel minibody of the 3D8 single chain variable fragment (scFv) showing intrinsic viral RNA hydrolyzing activity, cell penetration activity, and epidermal cell penetration ability. In this study, we examined 3D8 scFv's antiviral activity in vitro on three different H1N1 influenza strains, one Oseltamivir-resistant (A/Korea/2785/2009pdm) strain, and two Oseltamivir-sensitive (A/PuertoRico/8/1934 and A/X-31) strains. Interestingly, the 3D8 scFv directly digested viral RNAs in the ribonucleoprotein complex. scFv's reduction of influenza viral RNA including viral genomic RNA, complementary RNA, and messenger RNA during influenza A infection cycles indicated that this minibody targets all types of viral RNAs during the early, intermediate, and late stages of the virus's life cycle. Moreover, we further addressed the antiviral effects of 3D8 scFv to investigate in vivo clinical outcomes of influenza-infected mice. Using both prophylactic and therapeutic treatments of intranasal administered 3D8 scFv, we found that Oseltamivir-resistant H1N1-infected mice showed 90% (prophylactic effects) and 40% (therapeutic effects) increased survival rates, respectively, compared to the control group. The pathological signs of influenza A in the lung tissues, and quantitative analyses of the virus proliferations supported the antiviral activity of the 3D8 single chain variable fragment. Taken together, these results demonstrate that 3D8 scFv has antiviral therapeutic potentials against a wide range of influenza A viruses via the direct viral RNA hydrolyzing activity.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Gripe Humana , Anticuerpos de Cadena Única , Animales , Antivirales/metabolismo , Antivirales/farmacología , Antivirales/uso terapéutico , Humanos , Hidrólisis , Subtipo H1N1 del Virus de la Influenza A/genética , Ratones , Oseltamivir/farmacología , Oseltamivir/uso terapéutico , ARN Viral/metabolismo , Anticuerpos de Cadena Única/farmacología
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